My preference is for linear supplies, but today's switchers are not all
that bad. I'm baffled about your comment on the ultrasonics causing the
transistor junction to fail. Most power devices fail due to hot spot
(really the weak points in a reverse bias breakdown) or
electromigration. Modern switchers use power fets, so there is no
junction in the bipolar sense, unless you count the fast recovery
diodes.

The real problem with switchers was the poor level of protection
circuitry. [I'm lumping start up and short circuit protection together,
though start up can really be a problem.] It takes a great deal of
overhead to make a rugged switcher. Discrete designs couldn't add all
that "just in case" hardware than is common in good switcher controller
IC made today.

For my own use, I still build/buy linear supplies. I don't care if they
are big and heavy. But think how big a 400 watt supply would be in a
PC!

One problem with switchers is the noise they generate on the line
itself. You need to filter both the output and the input on a switcher.
For radio use, the line noise can radiate and cause QRM.