God only knows what bitcoin would be worth today had the shitcoin holocaust not happened. Ethereum did unrepairable damage to crypto when the token ICOs flooded the scene. Everyone and their dogs were buying these stupid get rich quick tokens.
You want bitcoin to go up? Simple. Quit buying shitcoins. Buy btc and hodl.
It's a little more nuanced than that. You're only thinking about the bear market cycle. The dynamic you're talking about actually pushes Bitcoin's price
up during bull markets. During the 2017 bull market, people were buying BTC and ETH left and right so they could invest in ICO tokens. Altcoin speculation definitely increased demand for BTC and helped push its price higher than it otherwise would have gone.
Where would Bitcoin's price be if not for altcoin investors scooping BTC supply off the market? I'm guessing it would be
lower than now.