But you have to remember that those aren't all the same thing. Of that list, only Watson is based on the personal conduct policy - which has its own set of rules and procedures. It wasn't even that long ago that the NFL elected to get involved in personal conduct of players away from the game of football or league-related activity.
Football-related discipline (Burfict) is a separate policy and Burfict's case was one of repeat offenses. PED and recreational drugs are also separate and have their own schedule of discipline where a violation results in an automatic, scheduled suspension. And the lengthy ones are based on repeat offenders. In Ridley's case, the league has a strong anti-gambling policy and views league personnel getting involved with gambling on NFL games to be strictly prohibited.
I think these kinds of graphics are disingenuous because they suggest that there's a single league disciplinary authority and it's not consistent or seems to value some things far more than others. That's not accurate - there are a variety of different kinds of ways a player can be disciplined and the ones that go directly to the game (on-field infractions, PEDs, gambling) have a history and league interest that is much more direct than the personal conduct policy. It's apples and oranges.