I've got a 2001 3.0i just like you.

Just now, as a test for you, I went out there (had driven the car earlier, so it was warmed up), unplugged the MAF and drove it.

After starting it up, no problems at all. As soon as I shifted into R (from P), the TRANS. FAILSAFE PROG warning came on. I went on a little drive. The shifting was definitely affected, much clunkier shifts, which makes sense, since the TFP warning is that the system thinks something is wrong and is using the AT in a safe mode to prevent damage. But other than the clunky shifting, the car drove fine. As in the engine seemed perfect as it always is, smooth, powerful, no missing, no initial problems, no high RPM problems. Just fine. Now, I expect there is a loss in efficiency and probably high end power, but nothing I could tell.

And if your MAF is unplugged, it does not matter how bad it is (unless it is obstructing airflow, in which case you could just remove the whole thing). It could be completely dead and broken and if it's not plugged in, it won't be making anything worse, and the rest of the system can run just fine without it, as my test above shows.

So as I mentioned a few posts up, if you unplug the MAF and the engine won't idle and (as I now have confirmed) drive just fine, you've got problems beyond the MAF. You may have problems with the MAF too, but it only makes things tougher to solve multiple things at the same time. So I'd focus on fixing whatever is broken outside the MAF first.

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2001 X5 3.0i, 203k miles, AT, owned since 2014