Considering that most altcoins are turning into scam after years of milking the unsuspecting investors, it will be difficult for new teams to get listed in exchanges while new investors today are already warned about new altcoins. The old ones are going to be in the market if they continue to keep developing.
Less altcoins that will successfully listed in exchanges due to them asking more money will discourage new scam teams and ultimately BTC will be the most bought coins making its price surge. Its not just going to be good for BTC for for all the remaining altcoins.
Exchanges are already doing this kind of filtering. There are way too many altcoins that simply just die and they don't want nothing with them. Others simply get delisted when their volume plummets. Did you see the number of coins listed in coingecko? Now enter the most popular exchanges and see how many they trade.
Everyone can make their own coin, doesn't mean it will be successful or accepted by the market. And yes, there are also the scammers.
Most altcoins are simply just ignored by default to begin with. They have to fight hard to get recognition, prove what makes them worth over the competition. They all say they are, but the market (aka. the people with their voting wallets) think otherwise.