Self-hosting has other drawbacks. Your need to maintain your server, you need a steady internet connection and a steady power supply. These are things providers like Proton and Tuta deal with for you.

Unfortunately, no iOS app… looks cool though

Uh nice! It‘s a little more work to set up the cloud drive to have the synced desktop folder. Overall very cool feature set!

Did some research and learnt that Qwant and Ecosia are working on an independent search index

https://www.eu-searchperspective.com/index.html

Does not answer your question but I just checked and you cannot customize the font in Mlem

Mlem for iOS let‘s you filter for keywords

Unfortunately, it uses the Bing search index. Would have loved a search engine truly independent from American tech companies.