I think Luis has identified the essence of your problem. Migrating from a very old Mac all the APPLICATIONS and software to this new and state of the art Mac M4. It is clearly struggling with something installed from the distant past that is no longer compatible. The "cure" as Luis described is to migrate over from scratch only user accounts and files but no settings and no applications. I have done this myself many times and reinstalling the latest and compatible versions of applications does not take long at all.
Several red flags in your Etrecheck:
Adobe CS4 pieces still installed: that software stopped receiving support from Adobe in 2013, the software itself dates from 2009, 15 years ago! The Adobe servers for it were shut down many years ago, one cannot even activate it. I have no idea if this is interfering with your computer's operation, but having things like this with all the associated outdated Adobe extensions and background processes cannot be a good thing.
User Launch Agents:
[Other] com.adobe.ARM.***.plist (Not signed - installed 2011-07-04)
Executable: /Applications/Adobe Reader.app/Contents/MacOS/Updater/Adobe Reader Updater Helper.app/Contents/MacOS/Adobe Reader Updater Helper
Adobe launch agents installed in 2011 are almost certainly incompatible for Sequoia.
[Other] com.valvesoftware.steamclean.plist (Not signed - installed 2013-03-13)
Command: ~/Library/Application Support/Steam/SteamApps/steamclean Public
Many posts online from people having problems with Steam, you have something for it dated from 2013! Almost certainly no longer compatible with Sequoia.
User Internet Plug-ins:
WebEx64: 1.0 (? - installed 1970-08-16)
This WebEx stuff dates from 2012 or earlier (1970? Huh?) and is almost certainly incompatible with Sequoia. It's an Internet Plug-in so might be impacting Safari, not sure about that.
[Other] com.mcafee.McAfeeSafariHost.plist (Not signed - Not found!)
Executable: /Library/Application Support/McAfee/MSS/Applications/McAfeeSafariHost.app/Contents/MacOS/McAfeeSafariHost
This McAfee software is still embedded and note above a Safari connection is still there ... you are having trouble with Safari.
Given that your Mac is permeated with these problematic installations, I would suggest the following:
Make a good backup, two or more backups are actually recommended.
Follow What to do before you sell, give away, trade in, or recycle your Mac - Apple Support
Note that the above step will completely erase all content from your Mac.
Then, with Sequoia installed, migrate only accounts and files, no settings and no applications and no software, from the backup. Then reinstall only modern versions of only the software you currently use and need.
If you aren't comfortable doing this yourself, you can go to an Apple Authorized Service Provider and they can do it for you safely.