It is just so critical to understand there is more to pH than, well, a pH reading. As Bang Guy points out...security blanket statements can lead hobbyists perhaps to be a litle less cautious than they need to be.
If you are dosing a 100,000g tank, and have a master lab (I also got to do the water chems using the HACH DR4000 spectrophotometer, calcium titration, etc...you can monitor a lot of things.
There are REASONS that a product may only achieve a max pH of _____ . and it is a complex chemical reason that may cause further impacts on the tank or animals. So whatever you add, regardless of how safe it is, should be dosed carefully and accurately.
Consider it like food. I mean, its food. Necessary, delicious...and too much of it will destroy your tank either within days or years.