I think your question is fair. I had my kids without even considering it, really. I think I was a bit clueless going into parenthood; my mum had died a couple of years previously and so I didn't have anyone who I could talk to about the realities of having children.
We have a couple of relatives in other countries. There's been no one in UK to 'support'. It's been hard, but we've done it, and 10 years on it's getting easier as the kids are more independent.
I remember talking to my sort of step-sister in law once when we were visiting family abroad, when our children were a couple of years old. She was describing how they had 3 sets of grandparents desperate to take the kids for a few hours/day/overnight and how they usually spent Friday going out and Saturday lazing on the sofa watching Netflix, child free. I was insanely jealous, because we'd not ever had that. We've never had anyone to take the kids for an afternoon. Or a night. It was 8 years before we got away for a night together as a couple. Every single thing I've done, I've had to plan what to do with the kids. Haven't got a relative who'll take the kids while I go to a hospital appointment or dentist or A&E with one child, so have had to do those things with children or alone, while husband has children. When we had our 2nd child, we had to figure out what to do with our eldest, who was 2, when I went into hospital to deliver. Ended up being a combination of nursery and husband, so I was alone.
It's also been ridiculously expensive. Childcare is expensive. I've also been jealous of friends who have family to provide free childcare, while we've scrimped and saved to pay for it, and not been able to go out and socialise together. We've spent a very significant proportion of our income on childcare. More than on our mortgage.
I'd do it again. It's all worth it. But no doubt it's been hard. On the other hand, we've raised our kids so far with absolutely no support from anyone so we can take all the credit! (And if there's any blame to be dealt, we can blame lack of support 😜)