Alt Text used to be easy to find - right click on a table, Format Shape, Alt Text.
I am presently updating our user documentation for PPT 365, and the ONLY way I can find to view the Alt Text form is to search for it, under "Tell me what you want to do".

I added "Alt Text" to my QAT from the "Not on Ribbon" list, but all that does is show the Format Panel, where Alt Text is nowhere to be found.

Alt Text is where it used to be for charts and graphics - my issue is PPT tables only.

I always accept Updates, so my PPT should be the current release.