Can't BTC just be forked again in the future?

Hi, I have a concern about BCH. If BTC gets bigger now, even if it is irrational, but say that the market cap gets even bigger. And then in the future they decide that "oh well the block size needs to be larger", but they don't want to sell all their coins and buy BCH, they can just make a new fork?

Why I think that might happen:

• Rich people already have BTC and they I will have same amount of coins if they fork, so why would they sell and buy BCH? They want to keep their "power".

• BTC network will be larger and if the miners are convinced BTC can just increase the blocksize.

• Even if it's a fork but not accepted by everyone, then all the BTC owners will have both old BTC and the new with increased blocksize.

My conclusion is that, if BCH should have a chance in the long run, it needs to gain size early, and if that is not happening faster than the market cap for BTC is growing, then it doesn't look good?

What are your thoughts? Are my concerns valid? Thanks!

Edit: I don't mean that I will do a fork, but that in the future, let's say the 100 wealthiest in BTC, will join together and fork and increase the blocksize instead of switching to BCH.