OP_RETURN lets you put up to 160 hexadecimal characters into the field.
Using letter count you get 48064 characters from a quick text grab of whatever you put in the OP
So 48064 / 160 is 300.4 so 301 transactions.
Text mentioned by OP doesn't use HEX, so your calculation is wrong. Assuming the Text use UTF-32 encoding, it should be
48064 character * 4 bytes (size of UTF-32) / 80 bytes (size limit of OP_RETURN) = 2403.2 (2404 transactions)
There I go forgetting the math again :-).
Seriously, although an interesting thought experiment I don't think many people are going to spend the amount of
BTC that I was talking about never mind 4X that amount of
BTC today to do something like this. Other blockchains with cheaper cost, I am sure are littered with stuff like this that nobody notices or cares about.
Although it's a couple of years old I think this paper is actually still an accurate description / discussion about it:
https://blog.coinfabrik.com/wp-content/uploads/2019/06/Censorship-free-Publishing-V2.pdf <-Standard warning just don't click on links verify safety 1st
-Dave