I have played D&D since the early 80s, played every version. I always roll HP for monsters. I will bump them up more in game if the party is steam rolling the encounters, and lower them if they are taking too much damage and using too many resources. To tell me that all goblins have 7 hp is laughable. They have a range.
The conversation given above regarding max DAMAGE does not equate to Max Hit points. IF I handed down max damage for every hit that would be really craptastically unfair.
Ive met a lot of people who've "played for 30 years" which usually means you played in middle school a couple times, twice in college, had a 20 year gap and recently decided to start playing again and have been having a hard time keeping a group together. How many games, groups, campaigns, and how many players have passed beyond the screen might be a better way to tack it. 15 enemies on the board that have different Hps for thousands of battles - what exactly is the method there and what on earth is the net benefit of spending that time for every single encounter? If you read what I wrote regarding that photo I mentioned that it was regarding the slider bar and specifically referencing damage as well, so I appreciate your reiterating what I said.