> Killing some processes to free up memory

This section is disregarding a key lore element, the inhabitants of the grid are programs. Killing a process in this context more likely has an interpretation of an attempt to stop an individual such as the villain Clu. I would say an alternative explanation is is more story based, with Kevin Flynn trying to stop Clu from the outside world but being unable to and instead taking the last resort of entering the grid when he knows it would be dangerous.

That's a good idea, but remember that, up until CLU's outright betrayal, Kevin had no reason to be concerned, and after it, he had no way back into meat space to run those commands.

Also -- unrelated, but a nitpick of the article -- Kevin was using the laser to come and go from the grid for a while before he got stuck there. The laser would have been pretty well-tested by the time he made/edited the last will and testament, so the article's explanation that it was his first use of the tech doesn't make sense. (He could have just spontaneously decided to update it though, which isn't too far fetched)