Loads of companies now have schemes supporting women in their return to work so in 10 or so years this will be the norm.
There's a rather large assumption based on not very much. OP would not be wise to make a decision based on that kind of attitude.
OP, first thing to remember is this is a very common feeling at this stage. It's felt by both women who later find they did want to SAH and women who later find they are happier back in work but were just panicking. Either could be you.
Secondly, nothing to stop you asking about part time. They've unofficially said no- ok. What might happen if you make a formal request? They can certainly refuse it but would need to show a business reason. If they do say no, would you like part time work elsewhere? You mention selling things which makes me think you might like some kind of sideline even if you did SAH- is that right? If so, worth thinking through all possibilities here. Freelance etc. It isn't necessarily a choice between your current full time role and selling a few bits.
Then consider what else might you do, both now and if you leave the workplace and try to get in. In terms of re-entering, listen to the experiences of people who've done it rather than people who haven't. It may well be that SAH is the right decision for you now, but given that it is difficult to re-enter later on, if you're going to do it then do it with full acceptance of the possible consequences.
I would also say that the numbers here make a difference. If you've been managing on DHs wages whilst dipping into savings, that puts a different spin on things then if you've been managing by only having one holiday a year instead of three etc. If he's still a fairly high earner himself it's likely to be a more sensible decision than it would be if you're going to end up in a top up benefits situation if you quit.