Interesting question. I am sure the sled guys will chime in. The table saw came first but the miter saw has been nibbling at its business. I like crosscuts on the miter saw because they are very safe. But they are limited to the size of the blade and that leaves out wide boards and panels. I think the track saws are nibbling at that business. Are the days of the table saw numbered?
I have both a miter saw and a TS sled, and find that each has some advantages. I don't have a track saw though.
I've got a DeWalt 12" sliding miter saw, and it's reach is still less than I can get with my Incra sled on my TS. There's inherent inaccuracy when you need to flip a piece to finish a cut, so for cutting something like a drawer bottom, the sled wins.
The TS's dust collection works better. Most of the dust gets pulled into the slot into the cabinet (depending on the type of cut). On the miter saw, the dust is thrown up and back, and while I have increased the vacuum port size to something at least 5x the original size, dust still flys around it.
The miter saw ***** at dado cuts. I use a height gauge to set my TS blade, and can use the TS sled to make tenon cross cuts where the miter saw just wouldn't be a good idea. (And I have a tenoning jig to make the tenon cheek cuts, but that's done against the fence, and not on the sled).
But these are all "exceptions". For most cross cuts, I use the miter saw.