If your ancestry was a tree, what people think of when saying this is the tree getting uprooted, when it really is more akin to cutting off a two, perhaps three growing seasons old branch.
Which is to say that not even in this teeny tiny way do you matter.
It is pretty crazy to think that for literally thousands of years, every single ancestral pairing, going all the way back to the first lil mud skippers that flopped up on land, have decided to produce offspring, which is ultimately the only reason you're even alive today.
And when it's your turn to uphold the unbroken tradition dating back millennia, you're just like 'naaaaaaah, fuck that yo'????
Honestly that's fuckin awesome! The point of life is your own personal experience, and you should absolutely do everything you can to push it in the direction of your choosing, tradition be damned. ✌️
The way I see it is that tradition is working pretty damn well on the whole. People are producing kids just fine, taking care of them as they grow and become adults is the hard part. That lineage you point to is the only reason I'm alive today, yes, but there are a lot of other "only reasons" I'm alive today that happened after I was born, and many of them were very much not from my biological parents.
Personally there was a lot of generational trauma in my upbringing and I don't wanna pass that on. These days I've taken that parental drive and repurposed it toward the adults in my community whose parents have decided to abandon them, usually due to being queer. It's different than having a parental relationship to a kid, but I'm finding a community guardian role is filling the same emotional need. The people I care for won't carry my name, but I didn't even carry my own name lol.
I used to struggle with the fact that nothing I do will likely outlive me, but now I feel it's just as worthwhile to make the present day better for the people who need it. I'd still love to work with kids, maybe teach or something, but being trans makes many parents less willing to allow their kids to be around me. I might foster someday, it'll be a challenge but I think it's something I'd get a lot more out of.
Jokes' on my ancestors, we've been getting through a bottleneck for the last 3 generations. All only children... at least on my mum's side, my dad's side's not faring much better with my generation and our kids
Each generation back from yours has a higher chance of not having their genetic lineage ended by you not procreating. Most people will have siblings so won't even be the end of their parents lineage, even less will be the end of their grandparents, I'd be surprised if there was anyone that could end the lineage of their great grand parents. Depending on your circumstances I'd say the only ancestors you have to worry about disappointing in a genetic propagation sense are your parents, and that's only if you have no siblings.