A real project will never stop running just because they are tons of shits projects now, just because tron (trx) or bnb is faster than Ethereum doesn't mean Ethereum project will fold or something, my main point is that shits projects are out everyday with no real use case, scammers are becoming much wiser everyday by building a project that seems similar to another successful project, we just have be careful when investing in new crypto projects,90% are created by scammers.
Scammer will stay in the market for as long as the community, investors and traders exist. Consider how many scam sellers are out there in the fiat market, you cannot eliminate them, either educate the community or they learn of their own after being cheated multiple times. I acknowledge what you said about new tokens that just because a token is faster doesn't mean the other ones will die because transaction cost is a very minor issue and while having low fees helps, certainly lots of other features are missing with TRC-20 otherwise it would have dominated over ERC-20 by now.
The future of crytocurrency is bright and I am very sure that in the near years it will be more developed that it is presenting now.It is getting more accepted by people globally unlike before,some industries have even started to acknowledge it like never before so definitely the best is yet to come for crytocurrency.
Nothing is going to replce bitcoins, I can almost guarantee that.
What USD is to other fiats is what bitcoin is for other altcoins, a set standard and to compare themselves against.