It's not a question of being hard on Costco. I bought this Dell desktop PC from Costco, Inspiron 3020, for a great reduced price in the second half of last year.
Part and parcel of this purchase was so-called Dell Technical Support. When they (Dell) consistently, persistently lied about all the difficulties all you good people were having with this feature, always denying that it was a known problem, even AFTER I forwarded this very link from Microsoft Community, and drove them to acknowledge the receiving of this link and its 30 pages of complaints and dialogs, I gradually came to the realization that Dell Technical Support was not being provided, despite my having paid for it.
There is a difference between being disappointed and being lied to. At least there used to be, 800 million years ago, like in 2018. There used to be a difference between not having expectations met, and being cheated.
I'm a software engineer, not a lawyer, but since I bought this hardware/software system from Costco, they ought to be held accountable for not delivering on Dell Tech Support.
The Costco Warranty Service made up for it, thankfully, by stumbling upon the Cumulative Preview update (HEY, what kind of double talk is that??) that made the problem go away.
Oh, by the way, you have to set the PC timeout equal to the display timeout. If the display turns itself off before the PC puts itself to sleep, the taskbar's autohide gets disabled as usual.
This kind of bug in general cannot be solved with full-blown debugging, because of the power management going on. It can normally be solved by inserting a bunch of "printf" statements into the code, so as to slash the area of code in question almost in half per iterative run. "Never say it can't be in that part of the code" and "Play the ball where it lies" is the essence of effective, efficient debugging, with or without the aid of a debugger.