Sure, but just because you run a relay doesn't mean anyone can actually discover it. On users/clients would want to use outbox model etc. I say that as I'm generally against the outbox model and sharing my usage patterns with a random relay. I prefer the model of 2-3 good relays you like and trust and being done. The other issue is spam and junk. The more relays you have in your client the more garbage you're going to see. Keep the list small and to those who do heavy spam prevention and it's less of an issue. For example. Primal and damus as read relays is horrible, it was ruining my feed. Filter their content through other relays who run spam prevention and it's nice and happy.

Although, the best paid relays work well alone because they aggregate and broadcast for you, and function as a sort of websocket proxy.