For most toy projects it’s perfectly sufficient, but once you get into complicated stuff it will bite you back.
Using an auto router is like building your software by copy pasting from stack overflow indiscriminately.
It's only when you get to higher speed or higher currents that an autorouter won't have the context needed to effectively route the circuit.
That's nothing that can't be incorporated into an auto router.
I suspect that if we made enough effort at the schematic stage to properly annotate all the nets and define the types of signals flowing around the board, an autorouter could do a superior job to a human (from an RF emissions and trace current sense).
I've never seen a schematic with that level of annotation though. So as long as the person doing the layout has to use external knowledge of what they're laying out, autorouters will struggle.
In theory you could make EDA software which incorporated a full circuit simulation which was then fed into the autorouter to provide a layout optimised for low-EMI and high efficiency. That would be nice!
Perhaps one exists, I don't know as I try to only use open source.
But yes ... probably not open source.
So ... while I can't say anything about PCB design in industry ... I can say that I tend to use a auto-router for my small DIY audio projects and it has never really failed me.
And ... if auto-routers are not used in the industry ... maybe that is something somebody on here should "disrupt" ... computers have become just too powerful not to be combative in solving some constraint path finding problems.
There was some external package that could do it, but at that point “screw it, I can route this board faster than reading the docs on how to deal with the autorouter” took over, especially since I couldn’t be sure anything I learned for this project would still apply for my next project if KiCAD later re-added an autorouter.