Short rests are important for the majority of classes, even wizards, clerics, and paladins. They shouldn't avoid short rests if they have the opportunity to take them.
But note that the Important Feature for Wizards and Druids (slot recovery) is more complicated than you indicate. Firstly, it only works once a day. Secondly, Natural Recovery is
specifically for Land Druids, not all Druids. The Druid's interest in short rests is
heavily dependent on subclass; Land of course always wants to take one short rest and would
prefer not to take any more than that, while Moon strongly prefers to take as many as possible. I'm sure other subclasses have their own concerns as well--Druid is just one of the rare cases where different subclasses have
really divergent interests.
Thus, instead of having a brute dichotomy--"wants short rests" vs. "doesn't want short rests," already unrealistic because, as noted, Hit Dice can be spent during such times--it would be better to note classes that desire
frequent short rests,
at least one short rest, a
variable amount of short rests, or who don't care. Wizards always want at least one short rest, and often don't want anything more than that.
I think quite often parties aren't taking short rests because there's no compelling reason not to take a long rest instead.
This, however I can agree with unequivocally. And I'm pretty sure this is in no small part because they made short rests an hour long, which means taking three of them in an adventuring day could easily be a quarter of all available time that day (assuming eight-hour long rests).
The game
expects people to take 2-3 short rests a day. From what information is available to me
and what statements we've gotten from Crawford and others, people
actually take around 1, sometimes none (if there's very little pressure),
rarely more than 2. And that does, inherently, disadvantage things that get a big chunk of their power from short rests (or from not resting at all; the Rogue theoretically doesn't care about any kind of rest, but that means they need
long days for their reliable damage output to matter.)
The designers, quite simply, assumed short rests would happen too frequently, and that people would stick it out through more fights than they actually do in practice. This is a perennial design problem, where the designers have
repeatedly, over the course of
decades and multiple editions, presumed that "sticking it out" type behavior will predominate when it empirically
doesn't.
