I know that a lot of fans are anticipating the days we see 4 quad programs and a handful of skaters are working on such programs as well. However, I think that it's simply not worth it.
Assuming a skater can do 4S and 4T, it'd likely be smarter to do two of their strongest quad and one of the weaker one. Let's take Max Aaron for example. If he does two 4S and two 4Ts then he can only do one 3A. In essence the second 4T would be replacing a 3A. 4T is worth only 1.8 more than a 3A, which in a close finish may make the difference of even two placements, however if for instance Max's Axel is on, he can get positives on it. Now, I've never seen his toe completed in a program, but I assume that any new jump would be weaker than a jump he has done for many years already. In my opinion, for a skater to do a fourth quad, that quad should be as consistent as their triple axel, or else it isn't worth it at all. There's no reason to take such a huge risk over less than 2 points. Just my opinion anyways