Hey hardwaresofton, this is exactly what we're planning to do on https://srv.io/ :)
The platform is mostly ready, and we're just finishing some infrastructure changes to allow the platform to run third-party applications safely. We are planning to include Listmonk in a second batch of the applications to release.
I personally enjoy working with Listmonk, it has replaced Sendy[0] for me.
[0]: https://sendy.co/
Just the other day I was wondering why there aren't "software maintainence/repair shops" as there are for hardware (PCs, gadgets, appliances). A tech shop like srv.io is exactly what I was wondering existed. Surely there is a market for it. I wish you (and your competitors) all the very best!
Glad someone else is thinking along the same lines! F/OSS could be so much better with the help of platforms — there’s space for a win win as long as the platform side just pares down the greed a tiny bit.
Prior to Listmonk I used Mailtrain[0] and like Listmonk so much I want to run it as a service (with 30% donated back to the Listmonk project of course) -- deliverability worries and initial setup aside it's just the kind of minimal tool I've come to love these days.
[0]: https://mailtrain.org/