NOTE: This is another take on a riddle/rhyme kind of puzzle. My previous one didn't get a lot of good reception, and so I've tried to make this one not fall to the same fate. Hopefully you enjoy it.
For a long time, this person was running
Something that many people were watching
Pressing buttons on a stick
Lights turning on in front of them
But these lights were different
They showed a person
This person who had done countless things
with a few others
3 of them known by a certain letter
Some of the things were good, some of them were bad
Some of them I can't even mention (and I'm glad)
They've popularized things that never would have had the traction
And instead would have succumbed to abstraction
But when in doubt, and you need a quick filler: VERWRPGLBHEERNYVGLNAQFHOFGVGHGRZLBJA!