This is a bad take. I will happily acknowledge the new term "slopository" which I had not heard before, while taking the author to task for malice towards theorists. STOC/FOCS/SODA, etc are not about "doing practical algorithms". If you want that, you go to ESA, ALENEX, or VLDB/SIGMOD, or any of the other more applied venues featuring this work. I don't think it's fair to just shit on theory because they don't do experiments---they're mathematicians, and it is fine to have absurd constants in your big-O as long as they are constants.
PS. I can have this view while simultaneously thinking that Ben is a badass.
As a theorist, it's sort of true that I "don't care" about galactic constants. I'm interested in the structure of computation for philosophical reasons. But I really do care about the model of computation.
To put it another way, the constants inside a big-O are not really constant: they depend on what you assume is a constant-time operation.
"Malicious" is an overstatement, but "exploit" is completely fair in my view. Theory with no possible practical relevance is useless, and I think a computational complexity result requiring arbitrary-precision arithmetic that is impossible to implement using any physical system qualifies.
If algorithmic theorists don't care about practical performance then why should we care about what they're doing? It's just a strange game they're playing, of no interest to anyone else.
It seems like rather than coming up with more "galactic" algorithms, a more useful thing to do might be to come up with a replacement for big-O that's not so exploitable, and to convince theoreticians to play that game instead.