I think the fact you “only know of coinbase” proves you know very little about what you are talking about, and have formed an erroneous conspiracy theory based on inadequate knowledge.
I don’t want to be antagonistic, but I have heard of many exchanges as I perused these forums through the years. FTX, Mt. Gox, Binance. So what probably should have said was, “It’s the only exchange I know that is still operating that I as a PNC bank customer can use, that I know of.”