I believe that there are characteristics of piano-specific climate
control systems being ascribed which are simply not there.  In my
experience these systems do not have the power to save or destroy
a piano; they are relatively low-wattage devices which are merely
there to help to moderate the extreme relative humidity conditions
and keep the pianos on a more even keel, in terms of tuning stability.

Is an older piano, which has survived the better part of a century's
worth of summers (at 80+ percent relative humidity), really going to
be done in by a little metal bar with a wet cloth wrapped around it?

For pianos of this age, spending money on humidity control of any kind
may not be justified as the market value of the piano would not support
this sort of expense.

While a whole home HVAC [heating, ventilation and air conditioning]
system with humidity regulation is by far the best solution, in reality
I don't believe the average person is going to undertake major
renovations to accomplish this, for the sake of their instrument.
A standalone unit (for a room) may work as well in some cases, but
the good ones can also be costly, not to mention noisy and greedy.

The biggest issues with the in-piano systems tend to be that they were
poorly installed, and/or not properly maintained.  If the custodian of
the instrument is not willing or able to make the effort of keeping the
system plugged in and watered as necessary, then better not to have one
at all.  Also, any system which is past its expiration date may be
defective or non-functional, in which case YES, it should be discarded.

Ian Gillis