An update to this:
Once again, this boot loop issue has occurred to me when the power was interrupted, or the TV was turned off correctly and moved, but after lots of wasted time and energy on my part, I was able to get it working with a hard reset with the reset button. I have seen mentions of this power interruption in other discussions on here. I would heed this information if I were a Roku software engineer. I also think that the rcovery mode not working right might be a good clue to work towards fixing this for the angry or upset customers who are having this boot loop issue.
I left the TV unplugged (onn. Model: 100012587 - 65" 4K UHD HDR10 Roku TV) for 24 hours and plugged in back in. It booted up, and went directly into Recovery Mode. But the Recovery Mode screen went from the normal green background to an orangish-brown, with text looking like almost unreadable outlines on it.
I then pressed the reset button for 15 seconds, it rebooted and went into another boot loop and ended up in Recovery Mode, with orangish-brown and messed up text output again.
I then plugged a network cable. I chose Wired (Ethernet) in Connect to the Internet, chose Update Now. It rebooted and went into another boot loop and ended up in Recovery Mode, with orangish-brown and messed up text output again.
I then chose Wired (Ethernet) in Connect to the Internet, chose Factory Reset, OK. It rebooted and went into another boot loop and ended up in Recovery Mode again, with orangish-brown and bad up text output again.
I then tried updating via the TV USB Updater website (tvupdate.roku.com) again. I followed the directions carefully, and once again, the system confirmed my exact onn. model. And once, I get the message: "Current software is more up-to-date. Downgrade is not allowed.”. This needs to be addressed for my model (onn. Model: 100012587 - 65" 4K UHD HDR10 Roku TV), maybe more brands/models, as In have seen people mentioning that for their TVs too.