I was a SAHM for five years although I always did some kind of work as I needed the money. So I worked as a playworker - took dd to work with me, catered children's parties, did some sewing and sold on ebay etc. I think if you want to and need to work you will find a way of doing it from home and there was a big list of excuses given above.
I teach so my job is useful and tbh everyone's is useful as their taxes pay for education, health etc.
I did not enjoy every moment of being a SAHM but it was easier than working, not saying it is for everyone before you all pounce on me, but for me it certainly was.
I stayed at home until just before dd started school and then worked part time for two years , this is my first year full time. I know my dd has to go without the undivided attention and care she had before because I work and there are times dp and I feel very guilty ( note I said dp and I because this is about parents not mothers , although dp is a sp and not dd biological father but that is irrelevant). But dd also loves me working, she is proud that I teach, often comes into work and I am more fulfilled and so in some ways a better mum. There are also material benefits to working, we can now afford to move away from a town we hate and dd likes the clothes, horse riding, holidays etc. I am lucky that I have the holidays to spend with dd and I try and do as little work as I can during the day during holidays. This week I will go in for two days while she is with her Dad.
I would not have another child while we are both working as I do not think it would be fair. My job is very stressful and I could not give a young child the time it needs. When we move dp is also going to work from home so that we have more time for dd though and rely on things like after school clubs less. I recognise though that not everyone is in a position to work from home like that.