It depends on what happens to you.
I was a Support Worker and then SW, if your family is none toxic then during times of severe illness, disability, having a disabled child, then your outcomes are much better with family support.
I know parents of disabled children who would have to beg the LA ( and usually not get it) to get a break, so they live even more stressful lives, without family help.
Again, if your DP/DH turns out to be abusive, having family does help, when you come to leave.
I was widowed with young children, they benefited from family support and so did I.
Children benefit from a good extended family, practically and emotionally.
I didn't have a big family, because I'm second generation immigrant and my Mother felt as the OP did, I had family in other regions, but she didn't bother to keep in touch. I do feel I've missed out and people think it's strange that you don't know your cousins etc. It's a very selfish attitude to take.
Ask anyone from an immigrant/refuggee background what it is like to not have anyone, accept for well meaning workers.
I've worked and had personal experience of people without family, Foster Care children, those from abusive families, those that have been rejected because of MH issues, life isn't anywhere near as good as someone's with a supportive family.
How many posts on here has there been from people who think they've had good friends, but in times of need they haven't. Being a high earner or having a good marriage doesn't mean that any of the scenario's that I mentioned won't happen to you or your children, who you've cut off from support.