Kyle was essentially batting practice (around 7.40 ERA) over 3 of the 6 months in 2021, and was bad in 2 of 3 months in 2022. We can't go on assumptions and feelings even though we love the guy, we only have the numbers to go by, and he was pitching poorly.
This is also an assumption, but I think it's possible they rode him too hard in 2021 after COVID. He only pitched 81 IP in the COVID shortened 2020 season, then they pitched him 181 IP in 2021. Your muscles etc can atrophy if you aren't pitching as much, his arm may not have been able to handle a full season load in 2021 like previous seasons, which may have caused the injury, and hurt his effectiveness in the last 2 months of 2021 when he was horrible because he might have been gassed.
Anyways, it's all speculation. It could be age as well, who knows, fans only have the #'s to go by, and there's some red flags. The K rate was also down last year.