The British attitude to flats is hilarious! I'm 44 and me and my husband have just moved into our first house, in London.
We've owned flats for years (mainly separately, though lived in husband's together for last few years). To be honest we're still missing living in a flat a bit. We have been lucky as we have had lovely neighbours in our purpose built 60s/70s blocks with loads of space.
You do get noise in a flat but you also do in our terraced house and we like to know there are people nearby in many ways, we don't like to feel too isolated. So it completely depends.
When I lived in my flat outside London I had access to a beautiful shared garden from my private patio too. We had a communal garden at my husband's flat which we couldn't access directly which bothered me more. But it was nice and pleasantly sociable in lockdown. In all our flats we have shared space with families (we have no children ourselves) and everyone has got on fine. Nice and diverse and less segregated.
Depends what you like. For years people have been asking us when we're getting stairs and a 'proper house', it's like some weird status symbol in this country. I've spent a lot of time with quite well-off families in Germany and Italy who raised kids in very nice flats and then bought a house in their 50s+ when they've saved more money, so they can have a sauna and gym or their own orchard etc or something else it would be hard to get with a flat.
In terms of leasehold/freehold, check out the management company as that's key. But if they are responsible and you have a sink fund then it's nice not to have to shell out all the time for works on your property and have certain things looked after. Leasehold is not an automatic nightmare, I can say after 20 years experience across 3 properties. One was more dodgy but two fine and I took a risk with the third.
It looks a gorgeous property with real character and few downsides even with children to think of. Live where you like the look of and that suits you!