I would argue that as long as the differences are objective and can be documented, it should be on topic. What you don't want is just a generic "Is it good?".
Some examples of possible changes:
Graphics: the most obvious one. That said, while most would expect the new AAA title to "look worse" on a Switch, many would assume more "dated" graphics should be fine. This is not the case, all it takes is some low-effort port and even simpler lighting/texture can look worse on Switch.
|PS4 / PS5
Performance: should be easy enough, but some games run very poorly on some systems. Shadow of Mordor was basically unplayable on PS4 for example
Censorship/"modified content": this mostly concerns "fanservice" and thus isn't really an issue - most of the time. But you have some odd cases where Sony censorship makes less sense. For example Doki Doki Litterature Club comes to mind - it is an horror game, yet the Playstation versions censored some death scenes.
Difficulty / amount of content: In some (rare) cases one version has more content than the others. This may be due to a DLC not released on one version, collaboration items that aren't available outside one platform and/or work differently. See things like Minecraft, especially when version specific items are involved.
Control Options: Most of the time this relates to the difficulty of using a pad for Console FPS, and whether it is possible to use a mouse instead. It also becomes very relevant for games that had console-specific control devices at the time of release (touch screen use, motion controllers, microphones, webcams etc).
It is also worth mentioning another side case. Sometime two consoles receive complete different versions of the same game. Just think at the Megadrive/Master System era - Sonic The Hedgehog on Megadrive is a complete different game from Sonic the Hedgehog on Game Gear / Master System. But in this case it is probably better to use separate tags instead.