DNSSEC is in a whole different league. But I'd be very skeptical of putting a one-liner from a generator into my DNS without understanding, at least at a basic level, _what_ it was doing. Understanding that also means you can do some manual verification - take a look at email headers to see how mail servers are responding to your configuration, etc. etc.
As for configuring a mail server, yes, that's definitely way harder. But these days, most companies outsource that to the likes of Google or Microsoft, until they get large enough to justify administering their own. There's exceptions to every rule, etc. etc., but every company I've worked at has either used G Suite or Office 365.
The result being: many companies have email services running, but don't have anybody whose day-to-day is understanding how it works and how it's secured.
As for configuring a mail server, yes, that's definitely way harder. But these days, most companies outsource that to the likes of Google or Microsoft, until they get large enough to justify administering their own. There's exceptions to every rule, etc. etc., but every company I've worked at has either used G Suite or Office 365.
The result being: many companies have email services running, but don't have anybody whose day-to-day is understanding how it works and how it's secured.