Mac can't detect TV OR TV can't detect Mac (HDMI)

I've tried everything. The power went out today while the TV was off and, unlike all the other times I was able to get the PC connected to the TV again, this time the same solution didn't work.

Here's what i've tried:

1) This is the solution that has worked in the past but no longer does. I would turn the TV off, then turn the computer off, restart computer, and then as it was loading to get to login page, I turn the TV back on.

2)

• Turn off the HDMI device while your Mac is turned on
• Unplug the HDMI cable from your Mac, then plug it in again.

Turn on the HDMI device.

4) Connect my other computer (Macbook Pro) to the TV. That didn't work either.

5) Hold ALT in System Preferences - Displays, and press Detect Displays.

I updated my Mac to Big Sur, and despite getting it back, I'm worried when I get another power outage (I get them frequently) this will happen again where I won't have another update to lean back on to refresh things. What do you recommend I do if this is the case? Are there any things you recommend I do differently next time?