The noise is often from backup power solutions like diesel generators that need to be turned on regularly. Maybe that’s what the turbines are? I can’t imagine a data center getting provisioned with a turbine as its primary power. But yes a data center can be silent most of the month.

Very open to being corrected on any of this, it’s just my own understanding but I’m not in the industry.

To my understanding (which can be wrong) these gas turbines are not backup generators, but used as primary or supplementary power sources during normal operation where the grid cannot supply (or when grid cost is unfavorable). In one clip (which is a bit sensationalist so I'll refrain from posting it as it may derail) shows a park of some ~24 large gas turbines - each of which sized like a small building - with about half in operation at that time.

Indeed, there is some noise from backup generators when tested (or in use), but with a bit of preparation, good palcement and sequential testing you can make that not too disturbing.