It depends on how badly Microsoft continues to fuck up Outlook (classic).

I don't use Outlook for my personal email, but I've used it in various corporate engagements and not been wholly dissatisfied. Newer versions are slower, more bloated, and unstable (though add-ins-- especially the Teams add-in-- contribute to that).

The most egregious regression, for me, has been the "Advanced Find" functionality (which was wonderful in the 97 thru 2010 versions) being changed-out for the god-awful search box within the Outlook window.

We could have said that for publisher a few years back. Its death knell has been sounded and microsoft aren't even offering any way for people to properly view or print their publisher files, let alone edit them.

The culture is correct, the new version of Outlook is hot garbage

Its the fucking federal government's policy. Basically it amounts to "pay microsoft as a form of corporate welfare", "permit but not really allow linux", and "this is how it has always been done".