I have a couple of crosscut backsaws I use mainly for cutting small boards to length. I use them in place of a mitre saw that I got rid of a year or so ago and haven't missed for a minute.
In fact they are probably the handsaws I use most. I use dovetail saws for intricate work and obviously dovetails. The back saw I use least is my rip cut back saw, though I'm glad I've got it.
I also have crosscut panel saws for larger boards.
I'd definitely use the crosscut backsaw for cutting tenon shoulders. But dovetail cuts tend to be small and I'll usually use the saw in my hand at the time - typically a dovetail saw.
I have quite a few hand saws. They are very cheap second hand. I bought a box of back saws for a fiver at an auction and have picked up most of my panel saws at a local house reclamation store very cheaply.
I'm trying to teach myself saw sharpening so having a few I don't mind junking is very handy.
My aim is to have two larger back saws (14"ISH) one cross and one rip cut. Then two dovetail saws, one 15 tpi and one 20 tpi. One day I hope my sharpening skills will be good enough that I can get rid of the extra ones I have.