Yikes, that’s disappointing. If the tracks are beat up by freight trains though, doesn’t that also affect the luxury riders / tourists? I guess there must be soundproofing for them?
Trains I was on in other countries (crowded or not, higher price tiers and lower) were always smooth and quiet rides at the least. Also, I only saw crowded trains a few times, so in most cases they were quite comfy as well.