Restaurant owners build a successful restaurant and then want to start a new one that they devote their attention and care to.
This means a lot of products/brands follow a parabola of quality over time, and what you're asking is pretty similar to How do I find out what's good before most people?
To which the answer is: Find a forum of enthusiasts and page through it.
If you don't want to devote that much time:
For restaurants, google maps is the reigning champion, while Eater is pretty good at finding whats trendy.
For stuff, googling for what you want and appending "reddit" and then selecting "within the last year" from search tools is still the reigning champ.
For TV/shows, google search shows 3 different ratings, and while I rarely agree with the ratings as an obective measure of quality, those ratings tend to be consistent with quality (although not scaled properly to quality).
You can use search engines to find the review on Reddit. Using some keywords like "{product name} reddit" should be helpful. For example, I want to know what other people think about a pair of boots from a brand. I will type "{product name} {brand name} reddit" on search box. Reddit has a bunch of reviews for boots because they have a dedicated sub. What I like about the sub is that the review comes from individuals and they share the review in details. The comment section also helps since some people will share or relate to the product. This is an example (I am not trying to promote the product, but just to give you an idea).
https://teddit.net/r/goodyearwelt/comments/czp035/wesco_pack...
I believe the same method can be applied to different product categories. If you can't find the review on Reddit, then I guess you need to find somewhere else.