So back in 2021, I looked up the tournaments requirements /prizes etc.
Not only did they have collection power requirements, and then later on SPS staked requirements, the prizes were also unattractive if people were to rent. (And the cost of cards were too high.) SPS rentals weren't around back then.
So deck for 8k or so (to be competitive.) SPS for another 4k why not (probably more cause SPS was higher.)
All to compete for a prize of $40 (if first place.)
Or, could just go play MTG: Arena, spend $25 for a chance to win 2.5k. (Probably won't, but in theory, it is possible.)
People in SPL have a dream of profiting by just doing nothing which is mathematically flawed. All the renting, staking ,etc, is just economic manipulation that provides zero value.
If SPL had a better prize structure, people can be motivated to spend.