None of those issues are baked into the design of the protocol. All of them have engineering solutions. Some clients and relays just haven't bothered because they haven't been a problem yet.
Do you run your own node? Seems from your relay list that you just added every relay that would accept you. If you keep adding any relays that accept you you can never be banned from everywhere. You have found the solution yourself while complaining about a hypothetical problem.
Every client can be a server. Theres nothing stopping your phone app from running a relay behind a reverse proxy. No app does this, because there isn't enough censorship yet that people would want the battery drain and downtime that it would result in, but you can fork any client with a local relay architecture (at least damus and amethyst afaik) and vibe code that into them in an afternoon. But you haven't, because you value the larp over building a solution.
