I've never worked for Tegna either, and I've never worked on the management level yet, but IME it's a two-way street as to what influences the editorial direction.
The corporate level of any station group will bring in consultants to try to guide local management into what they think is the best way to make a profitable newscast, and local management will then figure out how to do that on the more granular level. Tegna didn't hire Joel Cheatwood to just sit around. (Or on second thought, maybe they did.)
Corporate doesn't give station management carte blanche to do whatever they want, but corporate also doesn't "force" stations to do much either (at most companies, anyway.) WVEC backpedaled really fast on their 11pm experiment, and I'm sure that was a local decision.
I don't think you can pin these experiments on just corporate or local management. I know I posted on here a while ago an interview with Kyle Clark and Tegna's CEO, who was KUSA's news director in the 90s. I remember him saying that they're proud of trying all kinds of different ideas in multiple markets because every station and every market is different.
I don't think it's as easy as saying "every station needs to produce its own version of Next" because not every station is KUSA with strong management, not every anchor is Kyle Clark, and not every newsroom may want to commit to setting up such a specialized team for one newscast.
Also, a GM with a sales background sounds bad until you work for a GM with a news background who won't let the news director do his/her job.