IMHO audio gear reviews are mostly for the purposes of entertainment except where objective facts are provided as part of researching gear. That is not to denigrate as much as properly categorize the purpose. There are so few lukewarm, much less negative reviews...they are there for the pleasure of reading.
In terms of room, most reviewers know their room and their gear very well and if there is a difference by swapping out gear, they will hear it. I don't really audition gear until I get it to my room. After hearing it in their listening room, the reviewer will say "this isn't quite to the quality of my reference piece, but it punches above its weight and anyone would be happy to have it." There are like 5 reviews in the history of audio that don't say basically that.
Finally, I believe in trained or dedicated listening, but short of an actual disability in hearing (i.e. partial deafness) I don't think you need to have the ears of a puppy to gauge gear quality. As long as you have a good baseline from listening to your own gear intently, you will hear if there is any delta. Or you will think you do, if you spent enough on the upgrade :)