You would not have any products to use if it were not for the lab tests. There are fundamental differences between a polish and a cleaner. A polish has an abrasive in it (often very fine) and does remove some of the surface, the finer it is, the less it removes under the same circumstances, the coarser it is, the less polish, and the more surface is removed. A cleaner essentially removes the crud from the surface, leaving the finish of the material the same, and it's a good idea to choose one that won't have any degrading effects on the item being cleaned.
The lab tests give you a baseline against which you can begin to evaluate whether they are suitable for your needs. For example, if you needed a thinset meeting the ANSI spec A118.11 to bond something to say plywood, you could eliminate all of them meeting A118.1 and A118.4. Now, not all of them meeting any one spec are identical, but they do all meet at least the minimum specifications for that designation. It's up to you to decide the best one for your situation. So, use them as you see fit, but to knock lab tests shows a lot of ignorance. If you have some special circumstance that wasn't addressed in the test as designed, then it should be obvious that it's not going to be the differentiator you may want to know. But, the standards industry makes a reasonable assessment of what is required, then writes a test and develops standards to test the various products. This is where you can get into big trouble...using a product in a manner in which it was neither designed nor tested. An example of this is the reasonable use of a shower niche...given that it is covered in thinset and tile once installed, there is no way it will have standing water in it for days on end as the vast majority will run off, and what may get into the grout will evaporate in the meantime. The standards industry knows this, a 'normal' person won't have a hard time conceptualizing that, but some have big trouble with that concept.