As a man, I must say this is the most toxic thread I've ever seen. Full of horrible advice, from what are clearly women who have their own relationship issues.
For anyone reading this, DO NOT LISTEN to their advice. TALK TO YOUR PARTNER.
Single women, keep women single!
I would argue if YOU don't know why he hasn't asked yet, then YOU aren't ready for it. It's bugging you, and rather than discuss a personal relationship issue with him, you turn to random women on the internet? Does that really sound like marriage material, ladies? No, it doesn't.
Take some accountability, you are half of your relationship!
There are many valid reasons why a man may not wish to marry, or perhaps is hesitant. I'm sure if it was a woman saying they weren't ready, you'd all find it acceptable and provide a list of excuses.
There's likely something he wishes to see from you, which he hasn't yet. Some ongoing issue that he wants to see the pair of you handle better. Or something from his past that he hasn't opened up to you about... perhaps because you're on here, instead of talking to him!
For me personally, any time we argue over the smallest thing (think t-shirt not in the laundry level small)... she completely breaks the relationship down. Saying I'm no-longer our kids dad (he hears it), kicking me out the house, that we aren't family anymore. Then apologises DAYS later. This is obviously a huge red flag. But I love her, love the kids, and WOULD LIKE TO GET MARRIED. Just not whilst things are like that.