too many hardforks may destroy bitcoin
Hardforks are actually healthy in my opinion. It just shows how some(definitely not all) forkers are trying to think and try out a solution for the blocksize issues. Hardforks are only bad in terms of price and crypto-newbloods can possible get confused with them seeing lots of coins with "bitcoin" in their names.
I can only think of one reason. That is if all the governments ban it internationally.
The point of bitcoin is to have no government control. This will definitely NOT kill bitcoin. I can only see this causing bitcoin's price to crash due to all the fear that could possibly arise if this happens. Crash in price =/= dead.
I think that a real threat to Bitcoin could be that if prices keep rising and therefore mining being even more profitable and then many more people wanting to jump on that train and therefore starting to mine. This will lead to a massive energy usage that most countries wont be able to supply. Therefore governments sure will step in and maybe prohibit mining. As mining is something physical, its not that easy to do if its considered illegal. I think that this could become a real issue for Bitcoin and crypto in the future.
Good thinking; but I don't see this happening. More miners = more blocks being mined = higher mining difficulty. If we get a huge surge on miners then profitability will go lower, hence some miners will probably move to some other cryptocurrency to mine for profit. So in the end the miner count and profitability sort of balances out.