So as is so usual, this "updgrade" breaks things. Automation is now screwed, comments used to be able to be extracted but the Chats cannot. I had to implement a List/Power Automate/PowerApp solution as Microsoft refuse to implent a Read-Only permission on Planner tasks, but that is now broken due to not being able to extract the chats (previously comments).
For those of us that persevered with Planner (albeit with our own automation solutions to make it workable), we are now screwed. Many thanks Microsoft, another nail in the coffin.
You did NOT "listen to feedback" you actively ignored it, in fact you literally deleted many of the highest rated 'asked for' features and fixes. The very things that would have made your product workable. It seems like you are determined to drive your loyal customers away from your products through an inability to listen.
At least give us the ability to switch back to the old 'experience' so that we can carry on until you have finally got a product worth 'upgrading' to.