Definitely incorrect, I'm afraid.
The reason 4E was created (and this has been discussed in interviews etc.) was that Hasbro issued an ultimatum that either D&D would start making $50m revenue per year, or D&D would get vaulted for now.
4E's approach to design, particularly to going heavily-digital and heavily-subscription was very much influenced by the desire to hit this arbitrary revenue goal, set by Hasbro.
Now, 4E did not hit that goal. And 4E got canned because of that. But D&D wasn't vaulted as had been threatened. This is because of the other aspect of corporations - the mid-level and often even upper execs and their goals and pet projects are constantly changing (this applies to WotC themselves as well as Hasbro). Instead of being vaulted, 5E was allowed on the ground that it would take a very different approach, one that would minimize costs and risk to Hasbro, and maximize returns. An approach that actually proved largely successful from 2014 through about 2020-ish when WotC started to be interested in a more maximalist approach.
But certainly it's not 20 years of ignoring D&D, it was 8 at the absolute outside, followed by another what, 5-6 years maybe after 5E came out.
Hasbro/WotC c-suite have had periods of seemingly ignoring D&D, but not continuous ones.