A truly ridiculous amount of current work could be automated with today's tech and massive capital investment. And by today's tech, I don't even include current advances in ML. Every single worker at, say, a McDonald's is doing a job that could be automated with some capital investment. Retail stores, likewise. Self-driving vehicles are trivial when you stick 'em on rails, there's a big chunk of the cargo industry gone. Longshoreman-free ports, all that and more.

Then you get into the world of white collar work, where the "let's optimize society to minimize toil" solution, by and large, is to just eliminate the job wholesale. Accounting exists because the tax codes are too complicated, so streamline them and their jobs could be done by some API calls and Excel formulas. The entire finance sector is superfluous if money isn't the driving motivator in society. Entire militaries can be replaced by a "If we are attacked, we glass everyone we have even minor beef with" MAD systems. Trash pickups can be automated by tube systems. Food production is already largely automated outside of the produce aisle, so maybe we just cut back on foods that we can't harvest mechanically.

Frankly, the biggest sector that couldn't be fundamentally altered by a such a societal shift using just yesterday's tech is construction.