What if instead of scribbling li'l notes it was storing CSAM and other horrors for eternity? No biggy?
Discussion
That’s already the case. See eg.: https://www.theguardian.com/technology/2018/mar/20/child-abuse-imagery-bitcoin-blockchain-illegal-content
But I don’t think the Bitcoin blockchain is very well suited for this, so I don’t expect it to be widely used for this purpose. Not now, not when Bitcoin Core 30 is released, and certainly not if and when blocks fill up and fee pressure increases.
Your lack of concern for this is alarming.