Just to make a few points:
1. Her form since the US Open hasn't been great, but misses a few factors, such as that now being a Slam champion makes her more of a prize scalp for any opponent; or that last time out she was in fact playing very well in the face of an opponent on fire, before a minor injury caused her too many problems in the final set; or that maintaining season-long consistency is difficult in the best of times, let alone for somebody who has no previous tour-level experience.
2. She "changed her coach" in the sense that her US Open coach was only a temporary arrangement anyway. There was never any long-term prospects of their being together beyond the US Open. The press statement was unfortunately-worded, but the truth of the matter is still that they weren't going to stay together for very long anyway, and it was more about having a familiar face on Emma's first long overseas swing.
3. Raducanu's new hire, Torben Beltz, has impeccable pedigree so it'll be interesting to see how well they work together, but of course they'll need time together before judging.
4. The various sponsorship deals are important on their own, but Emma herself stressed that a red-line was that none of it should interfere with her on-court time. It's simply not true to say that she's lost focus, and certianly unfair to judge in on the back of a few tournaments shortly after becoming a record-breaking slam champion.
* * *
It was for CAC, but seems to apply to your post equally. Basically, people are too quick to write her off. 2022 I expect to be "disappointing" by the stellar accomplishments of this season, but it's more likely to be just a standard debut full season. It's only in 2023 and beyond that you can start to have a better idea of Emma's long-term future prospects, which in many people's eyes are still excellent.