this is a complex topic, where ultimately every bitcoiner will have to make up his/her own mind, thru accumulation, understanding, and application of bitcoin knowledge, as well as some guidance from knowledgeable people.

off the top of my head, you can start by listening to these videos:

there are talks about quantum resistant hard forks, but i think that problem is further away than a soft work.

I think you already got enough answers here from other stackers. I will add just a known meme that explain very well how a fork could happen.

Any successful fork of Bitcoin will still be Bitcoin. It would just be the majority of hashpower accepting a new and updated topology or architecture or whatever. To date, there have been a few attempts, but they never achieved a majority of the hashpower. The minority continue to mine BCH to this day for no other reason than to legitimize the duplicated coins that they created. They hilariously did so a second time with a fork of their own fork, further lining their pockets with duplicated BCH and called it something different, dumping on retail investors whenever they feel like it.

There would have to be some strong reason for doing so. Bitcoin remained unchanged through the blocksized wars despite many notable actors trying to increase the block size. Some say we need bigger blocks to scale with the number of transactions. I don't buy it now since we just saw the mempools clear and sats/vb at 1. Maybe one day it will be relevant though and things will get heated in the community.

It can be forked at any time by anyone. The question is when will a marketing campaign succeed in getting enough people to follow. We can only know this happened after the fact.