Who is the customer for a Model S? What fancy full-size sedan would they otherwise buy?
Certainly not the person who'd buy a BMW 7er or a Mercedes S-class. Model S does not offer the basic comforts required to compete in this segment.
Perhaps the person who'd buy a BMW 5er or a Mercedes e-class? Possibly, but the Model S is still an uncomfortable, noisy and cheap feeling clunker compared to those two.
It's not like the full-size luxury sedan market is doing too bad. We've got at least:
Audi: A8
BMW: 7er, i7
Mercedes: S-class, EQS
Porsche: Panamera, Taycan (sort of)
Rolls Royce: Phantom, Ghost
Bentley: Flying spur
Plenty of room for Ferrari to exist, but the Model S has been offering a low-end product at relatively high prices.