1. It's a problem for students who invested their time (and possibly money, but certainly opporunity cost) in this training. "Sucks for them, not my problem" is 1) excessively uncharitable, and 2) confuses personal interest with overall social goodness. Don't get me wrong -- it's totally understandable for you to say "is that really a problem that we should try to fix?". And in a lot of cases I probably even agree with you! But it's less understandable for you to simply say "that's not a problem".

2. Suppose you don't care about providing steady scientific employment for individual scientists but do value scientific progress (I find this position contradictory to the point of absurdity, but let's roll with it). Even in this case, cyclical funding cuts are still a source of waste:

a) society essentially wasted money subsidizing the education of people who are now not using their training (some might be, but probably many aren't).

b) funding freezes are often temporary, but by the time spending rebounds all those scientists you spent billions of dollars training have moved on to indsutry (research or no). So now you have to double down and train a new generation in order to make progress.