For the most part, I agree with your long and rambling post (welcome to the old man club). You can simply shorten almost everything you've said into: "bloat has killed prior editions; 5E has done an excellent job of keeping bloat minimal. We should not advocate for an increase in bloat."
Lowkey, I really dig your writing style; however, I think you should take some of your own advice and looked for more simplicity and less bloat.
When trying to make a point, start with the rule of 3.
First say what you are going to say; what point you are trying to make.
Then say it. Make your point.
Then say what you said. Say why this justified your point.
In each part, recuse if you need more detail. Repeat the middle part a few times as well if needed.
Don't rant on for 9 paragraphs about the sins of generic other people in generic other threads when talking about this topic without describing the topic clearly, or even saying what position you are taking.
While I, also, noted the irony of a lengthy post that in the end advocated a variety of minimalism, I found it a fairly easy read, certainly easier than some I have encountered that were half its length or less.
As to the specific issue of how best to structure an essay, while explicitly stating a thesis at the outset is an oft recommended and oft used point of structure, it ain't the only way to roll. There are at least a couple downsides to doing so. First, the reader may misinterpret the succinct, up-front assertion in ways that additional context might prevent. Second, it invites the reader who initially disagrees with the thesis (or who is just oppositional by nature, or who is experiencing some distress from the ill-considered consumption of a wafer-thin mint) to dedicate a portion of their mental effort to formulating counterarguments even while reading the arguments in favor of the thesis.
Finally, believing that there is one best way to present an argument, particularly in a rather casual environment such as ENWorld, belies, it seems to me, a certain narrowness of approach that might itself benefit from some rethinking.
All that said, I'll concede that a very long set-up without any hint about what the payoff was going to be could certainly try one's patience. Personally, though, in this case, from the subject line and the initial paragraphs, I did not find it difficult to discern the issue the OP was aiming at, or, in general, what his opinion probably was.