I've recently been trying to degoogle myself, and in doing so I'm going to need another email.
I tried ProtonMail, but apparently only business accounts can use SMTP, even though their features claim SMTP access.
I'm plenty fine paying for the service, but going from the $6/month to $12/month just to get notification emails from my server doesn't seem worth it to me.
I've not looked into what all else comes with Proton's Business features, but i'm not really running a business or trying to start one up.
What do you use? do you like it? How's the cost/features?
$10/year gets you what you need from Purelymail. https://purelymail.com I have used them for the last year or so and the service is fast and near real time with messages hitting my inbox (I use Thunderbird to download my mail).
I also just recently switched to https://purelymail.com after hosting my own for several years via Mailcow and a cheap VPS. The cheap VPS was more expensive than the $10/year for Purelymail and I was only using it for mail anyway. Nothing to maintain now and so far very happy with how easy it was to move everything over.
Also, they don't charge extra for additional domains so if you have multiple it's still $10. Only been with them a few weeks so can't say much yet for long term, but great so far!