This! I have the 14-core M4 Macbook Pro with 48GB of RAM, and Word for Mac (Version 16 at this time) runs like absolute molasses on large documents, and pegs a single core between 70 and 90% for most of the time, even when I'm not typing.

I am now starting to wonder how much of it has to do with network access to Sharepoint and telemetry data that most likely didn't exist in the Office 97 dial-up era.

Features-wise - I doubt there is a single feature I use (deliberately) today in Excel or Word that wasn't available in Office 97.

I'd happily suffer Clippy over Co-Pilot.