It's weird that people can't even remember the tenuous USP of this TLD is superintelligence.
If a .SI has nothing remotely to do with AI, or isn't realistic as a brand name for an AI company, then its end-user value is $0.
I can't remember if I've posted this or something like it before, but:
There are about 250k words in a standard English dictionary, and most people typically use just 20k to 40k.
So let's say there are about 20k decent single words and 1k (optimistic) good to great words, in terms of selling, but make that 5k for the sake of argument.
There are 1k NNN and 18k LLL, most of which won't sell except to domainers. NNNN has little value on non-.COM, outside obvious stuff like 1000, 2000, 1111, 2222, 1234, etc, likewise LLLL is 99% trash.
24k
Let's say (optimistic) about 15k great two/three word combos and maybe 1k brandables/made up words.
40k
And let's say 10k good to great single words in other languages where "SI" means something, though I've seen no evidence non-English speakers outside Slovenia are particularly interested in this TLD.
So that's ~50k domains that may have a chance of selling, but still mostly won't, especially when most have zero to do with "SI".
There are ~350k .SI names registered.
TL;DR: You can get away with murder on .COM, but if a non-.COM TLD has more than ~50k English names registered, you're already too late.