Without these records you're a lot more likely to go to spam, or get rejected outright. If you have questions about it, ask here or DM me and I'll be glad to help.
I think it is important to understand that email never will be very secure because the standard wasn't made with modern threat models in mind, if you want to communicate privately and anonymously, you need modern protocols like signal, i also use proton but only because I hate Google, i don't expect my emails are any more private than they have ever been. I use email only when it is required, I use signal for private communication, overlap is impossible
I recently migrated my email hosting away from proton. I paid for unlimited for almost a year, but I just couldn't take the missing features anymore. Maybe some of the missing features can be justified by security reasons, but some is just laughable.
If you want to use a proper email client, you need to host proton bridge in your local computer. You can only host imap and SMTP on localhost. Headless is not really supported, so good luck if you want your server to email you logs. Use VMs or docker containers? Fuck you.
On android, the only option is using their crappy mail client. For example, this client has not functionality to select all Mail from a folder if you want to archive it or mark as read. You have to select every single Mail one at a time.
Proton drive can only be used over the Webinterface or with some windows (gui) client. No automating your backups to be pushed there.
I switched to mailbox.org, which has weird 2fa but besides that makes my happy by just working with the damn standards. Not like email transfer is unencrypted when using STARTLS. Security is important, but for me personally, usuability has to be at least good enough.
Some services don't send verification letters to Proton and it's site banned by the address in fucked-up authoritarian countries, both for having less control over what it is and easy registration. I want them to explore some multi-site hydra approach so they can't get put out of the game that easily. Moving your emails here means you can't rely on a hope it would work tomorrow.
I don't understand why anyone is using gmail as their main mail account. I really don't like the interface and using it with 3rd party apps like thunderbird, K9 mail or any other client just sucks
Id like to move to Proton, but goodness are there no good usernames left. I'd have to go the custom domain route which isn't awful but it's just more effort
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.