Seems like Piped and Invidious are both on their last legs. Public instances on both services are pretty iffy, they go down fairly often now. Freetube works well on desktop but no real way to sync subscriptions and watch history to a phone. Self-hosting Piped/Invidious might be the solution but I don’t know if it’s worth the upkeep when YouTube is actively fighting against it.
Incorrect. Youtube does offer RSS, that is the point.
Above, you linked a page that said “This website lets you subscribe to RSS feeds for websites that do not support RSS themselves” to show that RSS works and now you are telling me that you don’t even need that service. Are you intentionally trying to confuse me? 😄😉
Instead of wasting your time in this conversation you might have tried just clicking on the link to see what it was. It’s simply a service where you search the platforms for a user and it spits out the RSS feed either as provided by the platform itself - Youtube - or by some libre mirror.