1. Many people now also don't really place any intrinsic value in human life compared to other animal life or the planet in general. I.e. a lot of people don't believe humans are superior or especially worth being preserved

2. Enough people are still having children that it seems unlikely extinction will occur due to their own decision to not have children

There are 8 billion people on this planet. I think the humankind will do just fine with a few people deciding not to have kids. In fact, it'd probably be for the better, if more people thought the same, given that we have 8 billion people on the planet.

That a huge stretch to come to that conclusion and stereotype people like that. Humans are not at risk of going extinct from a lower reproductive rate.

I don't manufacture shoes, does this mean my decision endangers the continued existence of footware?

i’m indifferent to that notion.

if people would like to have children that’s fine. if not, that’s also fine.

is there any reason why homo sapiens must be preserved, just for the sake of it?

India, China, and Africa are doing just fine.