You cannot out-work your TODO list. The only way to get ahead is to cut things out.
How to do it
The easiest way to cut things out is to stop doing things.
Tell people you can't do The Thing for them. Stop promising to over-deliver on expectations. Un-commit yourself from the things you've committed to.
But I said I'd do it
Unsay it: tell them you're sorry, but you've overbooked yourself and must gracefully bow out.
But it's important to them.
OR
But it's important to me.
Then stop complaining and do it. Or see above.
Overhead
Many TODO tasks involve "overhead"—that is, the research and communication related to the task that isn't actually the task itself. Because this overhead cannot be eliminated, deciding to not do something is actually more productive than finishing items on your list.
Procrastination
A great way not do things is to procrastinate until the items are unmistakably important and urgent. From school it is ingrained in us to get things done early. When you are a child with no responsibilities and a semi-infinite amount of free time, this is a good strategy. As an adult with competing responsibilities and limited amounts of time, it's usually best to deal with important things before you try to "get ahead" of the items that have not yet proven their value.
This is a re-written version of a post I wrote in 2022. This version carries the same takeaway with much less rambling. You're welcome.