"I don't know.
How many holes are needed before it ceases to be a stake? I don't know.
Irrelevant, anyhow, imho."
Sorry Roger, you first brought up the idea, so I would ask the same question to you.
"Yup, with or without the holes.
Mind you, I doubt the holes will change the weight very much, but they will weaken the stake.
(Looks like a Macpac stake with holes punched in it.)
Relevance?"
This stake has holes which enable snow to pass through, melt, and hold the stake tight. And let gritty sand pass through for additional holding power which, apart from those who say theoretically it shouldn't work, seems to work very well in practice. That stake is 10" long, 2" wide, and narrow in width with a curved flat surface. I suspect a few holes as illustrated would not weaken the stake appreciably in the field.
Maybe you can do an in depth review of stake design for BPL and out theory to practice. It would be boring but then opinions may become reality.