To designate a wardrobe as household storage in DS’s room?

No I think it's fine, we used half DDs wardrobe for DH's suits when she was little and before we got fitted wardrobes in our room, no point her having a wardrobe with a few dresses in and ours bursting at the seams!
I know people who have a desk in their children's room for WFH, it works while they're still babies/toddlers and don't really need their own space and don't have much stuff yet

I think it works fine while DS is very small, he won't even need a full wardrobe to begin with, but later on, his is the room that will need most storage.

Yes make it work for now. And if you are having guests who might enter nursery you can always do a quick tidy which I do anytime I’m expecting guests but in kitchen laundry etc. congratulations on your baby

I wouldn’t move your dressing table either. It may be very handy to have baby playing/laying on floor or in crib while you are getting ready. Baby sees you and is content and you see baby and can get ready without worry. It’s your house not a magazine. Use the space as it best suits your life today. And of course use this conversation to do decluttering together or just get rid of his shit without him knowing like I do.

Yanbu.
But as someone who has also done this, i would strongly strongly strongly urge you to declutter now because it will always be an unappealing job and its much harder to do when little kids are around.

They also end up with more and more stuff as they progress past toddler age and so you will thank yourself later if you get rid of stuff now and have that space to dump his extra stuff in.

Looks in DS2's room. Shrugs. He sees to be perfectly fine, and surviving secondary school just fine with the Christmas decorations, fancy dress stuff, out grown clothes and charity shop stuff on the higher shelves of his wardrobe. He has plenty of space!

Likewise, our room has all the spare bedding and towels, and all the holiday stuff.
DS1 just has his stuff due to the lack of storage in his room.

Surely this is just part of living as a family???

I didn't even have my own room, shared with first the older brother than the younger, until I was 16. We had one wardrobe between us.

As others have suggested - it's fine. Your DH is being a nerk.

In DS16’s room we store suitcases, spare duvets and board games. No way could we manage if he had exclusive use of the storage in there for his stuff!! Your DH needs get real!!

It's fine.

Being the youngest in my family, I had the smallest bedroom, and in it was a quite large 2-drawer chest of drawers. The bottom drawer had my stuff, but the top drawer was packed tight with my dads stamp and postcard collection!

From the time we moved into that house, when I was 6, up until I asked for his stuff to be moved out when I was about 11. It was in there.

To be fair, it didn't bother me, and also fair play to my parents, as soon as I asked for his stuff to be moved out, they did it without a quibble.

I have a set of curtains and a dvd player stored in dc's fitted cupboards. Their room has the most storage in the house, and they don't have huge amounts of clothes, so we use it for other stuff.

Growing up I had a roll of carpet under my bed for years, (dad was going to fit it one day...) and we had mom's longer dresses in our wardrobe because hers was a half height built in one. That's family life, surely?

Your Ds will be part of the family and household, so completely appropriate to store family/household things in his room. Does your Dh think you are about to give birth to royalty 👑 ?

Your other half has lost all sense of reality.
Lots of children share rooms.
a baby won’t have any sense of what is in their room for years or care. Having a bedroom that has no single item in that ‘belongs’ to another part of the house is nothing to do with what a child needs or deserves.
i think he might get shock with how little use that bedroom will even get for a while!

We have a similar set up in both my DC's rooms. Two floor to ceiling cupboards in each room. I use the high sections for general storage and they use the lower section for their things. They are teenagers now and have barely even noticed this set up because they have enough space anyway.

My teens’ wardrobes have always had some family stuff in them eg camping gear. As they have the space. They have never been precious enough to make a fuss over it. I daresay your baby will cope!

It’s totally fine! My middle child has the biggest bedroom out of the 3 kids, and has 2 fitted wardrobes either side of a chimney breast and a bank of cupboards above them. He has one (very good-sized!) wardrobe for himself, and the rest of it has the family’s out-of-season coats, sleeping bags, some suitcases (big ones are up in the eaves), and other bags.

Teen DS has a built-in wardrobe with three sections.
One is for his clothes, one is for his junk, and one is for household linen, towels, bedding etc. He really doesn't care, or need the space.
Your DH is being a bit weird!

Does dh think ds will be ringing Childline about some stuff in a cupboard?
He is nuts.
Ds has a whole cupboard full of camping stuff in his room. Isn't mentally scarred...

I thought you were going to say DS is a teenager 😂

Of course it's fine for a baby's room

If your DH thinks it's unfair empty his wardrobe and store household stuff and he can get rid of his stuff.

Unfair on a baby! Heard it all now.

Of course it’s fine! Your ds won’t need all that space himself for ages, if ever. My middle child’s room, which was also the baby room each time, has two lovely bookshelves that for a long time had our grown up books on, as the kids couldn’t reach the shelves and their books were in baskets they could reach. But a their book collections and their height have grown and my DS has needed the self space I’ve moved things round. But that is 9 years down the line! And he also has a chest of drawers in his room being used for general storage. But not at the cost of storing his own things or having his own space.

Absolutely fine. We use a cupboard in my dsc's room for household storage. In fact they mostly dump their stuff on the floor when they are here so I might take over the other one