Of course. I have nothing against Fediverse server admins setting up a Patreon —ideally Liberapay— or something similar to receive donations to cover running costs. I have and continue to contribute financially to indie devs or server admins when I can.
Not everyone will do that of course. But there again, running stuff at a small scale shouldn’t be crazy expensive either. The operational costs of keeping a microblog or indie site running are little to none. I host my blog and all of my side projects for free in a cloud provider.
Running a Fediverse server is more expensive. Last time I looked into what it would roughly cost to stand up a barebones stack to host a Mastodon server in a public cloud, it was like a hundred bucks a month. Not cheap but it may be big enough to house a couple thousand users. If at least 0.5% of your userbase donated some money to cover running costs, you might be ok.
Alternatively, if you have a server lying around at home, loads of people self-host at home, which is a tad cheaper.
I’m not saying a fully decentralised indie internet wouldn’t have its shortcomings, of course. I’m just saying I’d happily take that over the current state of the web.
I’ve been using Tuta Mail for a few years now. No complaints. Most of the features you would expect. Lack of IMAP support is kinda disappointing but survivable. Their email security is very strong though — they encrypt every part of your email, including subject (some providers only encrypt the body). They’re also rolling out post-quantum encryption of email data at rest, which tickles my crypto nerd side.
They’ve still a loong way to go to match Proton’s product suite though, as they only offer Email, Contacts and Calendar for now. They’re working on Drive storage next, which is the main reason I currently use Proton.