Ok. What exactly are they doing, creatively to make the game more popular?
Jeez. Where would you start?
To begin with, the entire design of 5e was predicated on two simple things-
First, ensure that elements from older editions were included. This is the whole bit about making sure that "legacy" issues were accommodated. In some cases, they included the legacy elements but largely decoupled them from the mechanics (such as the alignment system). In others, they chose to go with a legacy elements that were familiar ... such as the strong class-based system (albeit weakening niche protection). The reason for this from a design standpoint was simple- in order to ensure not only that the edition was "fresh" to new players, but also to attract back experienced and wayward players who hadn't played in a long time, or who had been playing other games but would feel some sense of familiarity with 5e.
Second, they made sure that the system was descriptive and not prescriptive. While 5e in its core books suffers from a deficit in teaching people how to play (you really need to use the Basic set, or starter sets, or youtube videos for that), the great advantage of not telling people how to play is that it allows a multiplicity of playing styles to coalesce under the 5e banner. The strength of a lot of great games is that the rules force you into a narrow range of prescribed playing, which is great, but also reduces the overall ability of the game to adapt to different playing styles. 5e, on the other hand, can be used in anything from a dungeon grinder to a light-hearted fey adventure, and there's no "you're doing it wrong."
These aren't mistakes; there are design choices. Moreover, even the slow pace of release of crunch is a deliberate choice; previously, editions quickly became saddled with too much crunch and too many options competing with one another (cough 3e cough). 5e has remained relatively clean over nearly 10 years. Tasha's changes, for the most part, were introduced and aimed at the newest generation of players- the younger players who had started in 2014 on who weren't as burdened by legacy expectations, and they all make sense from that perspective. Less race essentialism and a grab-bag of new feats and spells.
The whole enterprise seems set to continue ensuring that while there will still be more crunch on the character (and combat) side than many other TTRPGs, it will never approach the crunch of, say, 3e. And the focus, instead, will be on what people will do with the characters. This is more about stories (in the Critical Role sense) than it is about chargen and optimization.
IMO, YMMV. etc.