The logical fallacy where you dismiss someone's concerns or complaints by saying "it could be worse" is called the relative privation" or "appeal to worse problems" fallacy. This fallacy occurs when someone argues that an issue is not significant or does not deserve attention because there are worse problems that exist.
Also theres another fallacy where you focus on dats that support your argument and ignore arguments that dont.
Some problems may be better in modern society but some problems may be worse.
We evolved to deal with suffering, so, absent suffering, we invent our own. Appealing to worse problems can be an attempt to subvert that mechanism by forcing perspective. Subverting it is good since the mechanism is stupid: it's programmed to strive for a deliverance/salvation from problems which it guarantees can never arrive since that state is like the dog catching the car.
Another approach to subverting it is religion. :p In Judeochristianity, "don't worry, you get the salvation; it's just not in this life". In Buddhism, "the salvation is an illusion that you can tap into at any time if you meditate hard enough".
Also theres another fallacy where you focus on dats that support your argument and ignore arguments that dont.
Some problems may be better in modern society but some problems may be worse.