Good question. I chose it initially because it was open source and way easier (in my eyes) than Apache. I don’t recall the others being an option at the time, or I was not aware of them. nginx does what I need without complaint, so I haven’t switched.
It’s feasible as long as all the stuff you want to auth supports oauth, oidc, or saml. It might be a bit overkill for your use case, unless you have a bunch of services you didn’t mention. Keycloak has a bit of a learning curve, but works great once you get past that.