I for myself can say yes.

It is much cheaper than a package on a ISP, where you pay monthly your Domain and most time have limited mailboxes.

Why should I pay 10 or more Euro for my ISP, getting randomly mailboxes without DNSSEC, DANE, DKIM and so in, when I can get all of this for monthly 5 Euro. Ok I pay actually arouns 8 Euro, but have a fully featured plesk, which is nameserver for my domains, yes I said DOMAINS. I have all actually security features working, all my domains are best rated by security checks, have automatic reputation check and prevention.

So why pay 10 or more for mid-class ISP mails or around 8 Euro for full featured own plesk, where I can host as much mails, subdomains and other.

Ok, I'm an IT person, but my configuration isn't that complex and also I dont have to do time taking maintainance, because plesk is automatically updating most things.