I don't think you've dismissed anything, but the next valid questions are "why did HTC do this?" and "what impact does it have on the user?".
It sounds like the answers seem to be "because sense takes up the majority of the 1gb of ram leaving too little for the stock settings to be able to work" and "some users are really frustrated by not being able to keep multiple apps open that older phones had no problems with".
The answer is not the conclusion that I personally drew from Jerry's article which was 'it's a design choice by HTC (like color, or screen size), not a problem that needs correcting' (which I may have misinterpreted, but that's the feeling I got reading it).
Not being able to multitask the browser along side another app is an issue that should be called out as a "con" and highlighted as a potential significant annoyance, not an aesthetic choice open for various subjective feedback on. That's a pretty big step backwards and not what one might expect from a flagship powerhouse of a phone and would certainly impact my buying decision if this affects the evo 4g lte as well.