I'd agree people are trying to make it a "job", but then you'd think they would want/need to do a good job to get and keep viewers.
That's the easy part.
As in the review style you mentioned -
You might know they're talking out their backside, or have not done their research properly, but they're talking enough sense to show they know more than most of the people watching their video... and those will be their repeat viewers, at least until they come here and learn enough to move on, but there will always be more to keep them in place.
Even the well-known experts who really do know pretty much* everything still make mistakes or miss stuff out. The spit-hot ones will issue corrections, though.
End of the day, just use your noggin. Most reviews give enough info for me to extrapolate and get an idea of whether I'll like a light or not... even the ones where it's a kid on a shaky iPhone camera in his bedroom, "umming" and "like, err, like-ing" his way through basically just regurgitating the enclosed product manual.
*There is always someone in a dark corner of an internet forum who knows better, anyway...!!