Can I tell my MacBook Pro to forget all previously known external displays?

I use a 2020 MacBook Pro M1 13" for work, where I work from home for a few days of the week. In both environments, I use external display, keyboard, and trackpad, with the MacBook lid closed standing in a vertical mount.

My desk at home has a LG 34GP950G monitor (3440x1440, 180Hz) which I've been using with a USB-C to HDMI cable for a few weeks now with absolutely no issue. The cable itself is HDMI 2.1 certified, but my monitor is only HDMI 2.0, so I was only getting 100Hz refresh rate.

When I sat down to work at home this morning, my LG monitor simply would not show any picture, instead showing a "no signal" message. When I opened the lid of my MacBook, the external display turned on for a moment, and I see my macOS desktop for about 2 seconds before it goes back to "no signal". Meanwhile, the Settings > Displays page still shows the external display as connected and active. Changing resolution and/or refresh rate does not do anything.

As an alternative, I do also have a USB-C dock with an HDMI output, but this has severe limitations that make life difficult... More specifically, this limits my LG monitor refresh rate to 50Hz and I see what I can only describe as "constant color shifting" as I switch between applications.

Furthermore, I accidentally selected an incorrect refresh rate for my LG monitor while connected through my USB-C dock while my MacBook Pro lid was closed, and now it will only work in this configuration while I have my MacBook Pro lid open.

This was not an issue because I prefer to use my USB-C to HDMI cable anyway, but now that this has stopped working, I'm stuck with only this crappy USB-C dock with the laptop lid open and horrible colors everywhere.

How can I tell macOS 15.1 to just forget about all previously connected external displays? I want it to think it's never seen my LG monitor before in ANY configuration, so that I can have a "fresh start" of sorts for this. With all the issues I'm running into here, I feel like this is the best solution.