Doesn't work, crashes product saving,

How do you know that the error wasn’t at your end? Why didn’t you try to contact the plugin’s author about this by posting a topic in the plugin’s dedicated sub-forum?
Try reviewing:
https://pippinsplugins.com/how-to-leave-a-good-bad-review/
https://chrislema.com/theres-wrong-way-give-plugin-feedback-wordpress-org/

Yeah, I was hasty with that, but after checking plugin after plugin and getting through tons of different WP issues sometimes I got impatient, especially if I see such serious issue. I deleted the plugin and moved on to the next one and the fact is, most of plugins I tested works well. Well… not always the way I would need or like but they don’t crash the whole site. This one did. This is the most serious issue that any plugin can have.

From other reviews I gathered that this is most probably some singular bug because other reviews are positive and don’t mention it. But I don’t have time to post it on support and figure it out how to fix it. So posting a review is the quickest way to let that something like that happened.

Other plugin reviews are full of such situations and I learned that with the major positive feedback I just have to try it myself, because although it didn’t work for someone, it is rather more likely it will work for me as for majority. Such bad reviews “doesn’t work, crashes the site, etc.” are for me like small memos of individual issues rather then opinions that matter.

But you are right that in ideal situation such reviews shouldn’t be posted and it’s better to put it on support forum and let others decide if responses helped or not.