Mission Control/Launchpad is inexplicably activated

OK, @leroydouglas, I tried the Safe Boot method. The problem still happened. So then I tried the new user method. I created a test account and proceeded to write for an extended period of time in Pages, Bean, even Apple Notes. The problem did not appear. Now I'm trying to see if it happens back in my original (admin) account. So far, it's behaving.

I am fairly certain that I wrote enough in the test user account to see if it replicated. Of course, I'm now a little irritated that it ISN'T happening in my admin. I mean, I'm glad that it isn't happeneing, but if the problem has indeed gone away, I'd like to know what the issue was in the first place (I'm kind of continuing the test just to see if it reappears. I'll shut up soon and resume normal writing elsewhere.)

So, if it does reappear, then then WE INTERRUPT THIS POST TO REPORT THAT IT JUST DID!!!! So, it would appear to be my admin user account. Now I have to look at what you said to repair the issue.

You said: "unplug all non-essential  peripherals when testing"

I had done that before testing.

 You also said: "Uninstall all third party apps that are Cleaners/Optimizers/VPN/Anti-Virus

all known to cause issues on the macOS"

Ok, I will try that. I have no VPN, I do have Avira Free AV, but I can delete that. I suppose I can delete the cleaners (Cleaner One and CCleaner, free versions for both.) The only optimizer I have is Onyx, which I've had since I've ever had Macs (nearly 20 years) and deleting that hurts my sentimentality for software. But all I ever have it do is run the normal, routine system things, so out it goes, I guess. {{Sniff}} I actually think I have one or two others, but (IT DID IT AGAIN!!) I can delete them. I'll just assume MacOS does it's own system optimizing in it's own time? (If you or anyone else can respond to that point, thanks!)

Anyway, off to delete a bunch of stuff. I'll report back later.

Nothing has worked except a test user account; it would appear that the Admin account has an issue which no solution suggested, rebooting in Safe Mode, deleting certain apps and whatnot; I even, at long last, managed to reinstall MacOS Sequoia. Nope, the Mission Control launching still happens. I've found no workable solution to repair an Admin account.

I did install a free, 7-day trial of "Clean My Mac" to see if that would do anything (it did delete the massive amount of Purgeable space, although it took 3 tries.) I'll delete the trial sometime before Saturday.

I may wait until after Tahoe is released and see if the issue persists; if it does, I'll curse the Apple gods and then perhaps create a user account just for writing and other creative work.

This has been frustrating to say the least. I've dealt with this issue long enough, another couple of months won't matter.

Thanks, but nothing in there helps. I have turned off all trackpad settings that have anything to do with this (as I stated in the boldface part of my post.)

To repeat: as I am typing Mission Control or Launchpad get suddenly activated despite my having disabled every single keyboard/trackpad function that has to do with this. It's distracting to say the least and disrupts my train of thought.

Yes, including "Hot Corners." AFAIK, I have exhausted every single option, except for trying leroydouglas's second suggestion, which I will try, if not tonight, then this weekend. After I do that, I'll post the results.

It is still happening. i was going to report this yesterday but figured, maybe wait (foolish, yes.)

I think I read elsewhere that another solution could be to reinstall MacOS. I will do a Time Machine backup tonight and try that.

Thanks for your help!

I can't do it. I have insufficient space on the HD; apparently it needs nearly 50GB of space, I only have 32-ish free.

{sigh.} I'll see what I can do about freeing space. In the meantime I'll endure the issue, ocassionally getting annoyed and cussing whatever's responsible. This is my worst continued experience with a Mac in the nearly 20 years I've used them.

And so I deleted or moved to an External HD the nearly 17GB of data I had to. Now it says I need to remove 21GB. I have 42GB free, 14 GB Purgeable (I mistakenly assumed that MacOS will get rid of the Purgeable since I read "that's what it does" when it needs more space. This is aggravating. I've wasted enough time trying to solve this; I'm done. I'll suffer until I need a new computer.

Well, I am trying another keyboard, a wireless Logitech we had laying around. The problem has not made its appearance.

So, a different keyboard works, and a test account works. How can the two be connected? The admin account has some kind of problem controlling the built-in MBP keyboard ever since Sonoma was released?

Thanks! I will look into this!