A squelch is normally only used with FM, and sometimes AM.
With SSB and CW, it cuts in and out way too much..
Would require a delay circuit to make it practical at all, other than AM and FM.
I have used transceivers since 1959 (FM taxi Service), and otherwise from early 1970s.
I don't mind the noise. If it gets too much, its time for a break anyway.
I'll add that squelch can be good with any reception that uses a constant carrier, but is not very goof with no continuous carrier.
Or maybe where you have a delay circuit and don't care about weak signals that can drop out at times
I rarely use the squelch on my Icom 706 MK II G, other than with FM.