This is not even the topic of discussion. (Disclaimer: The rest of the discussion here is tangential to the original post.)
While I have no qualms with you using Suckless. As a person who has used suckless tools (dwm, st, tabbed, etc) for 2 years straight in the past. There are simply more performative and easy to work with tools and programs. I spent a few weeks worth of time in total over the 2 years trying to configure dwm alone to match with my workflow, applying and maintaining over 40 patches from the website along with some of my own written patches. When I switched to awesomewm, I easily reproduced my design in a single day and extended it further w/o much effort. Sure, the codebase is much bigger, but it is a fair trade for me if it reduces the time I need for configuration as a user while giving me the same performance.
I had, more or less, the same experience if I talk about st which I later replaced with Alacritty. The socket mode also helps me save RAM space when using Alacritty as I tend to have multiple terminal emulator instances open.
The stock distributions of suckless tools are always unusable unless you patch them to hell at which point they are definitely going to stop being suckless unless you really want to brainstorm and spend more time on it. (Read the Suckless Principles.) You can argue that criticizing Suckless Tools is in essence criticizing yourself because they are intended as canvases to paint on by the user. For me, it’s just a waste of time and I would rather go for a program that is less hassle to configure & maintain.
Honorable Mention: Suckless Devs endorse Neo-Nazis in their team.
At the end of the day. The main thing people should be aware of is that Cloud Storage is basically you keeping your data on someone else’s computer so you must assume as a rule of thumb that that data is vulnerable even if it is allegedly encrypted.
Now Proton has its own share of controversies which make its advertising of Privacy less trustworthy, at least in my eyes. I won’t go into details so feel free to do your own research, it will only take a couple web searches.
I personally also use Proton Mail for work but I always try to never communicate anything through it that I feel is risky in the context of my critical personal info.
Self Hosting is not the best solution when it comes to Mail Servers because of the whole domain trust issue yada yada as far as I am aware. (I don’t have the resources or the money to self host so I am going through someone else’s shared experience.) But it’s definitely the most concrete solution for privacy.
I understand your concern. All I can do at the moment is establish a private channel, if it is possible for my friend, so that you can verify the legitimacy. Feel free to contact me via Discord or Matrix.