So why is elo decay even a thing anymore?

Currently, you aren't even required to climb and maintain a climb to obtain season rewards. Basically, just hit gold V (which really ISNT that hard, anyone who is able to play at the average elo silver 4-3 can get G5 just by grinding), sit on your ass and collect season rewards. Meanwhile, plat + players must play a ranked game every 28 days or face decay and they get the same bundle of rewards except different borders.

Now don't get me wrong, this isn't me hating on Gold players or their rewards because as a diamond player, if I didn't care about keeping the rank, I'd still decay back to gold and still collect rewards. But at this point, why even bother? Everyone gets the same rewards now, so why are plats+ forced to play? I get why master tier and challenger tier face decay because of the ladders but anything else seems silly. If as a diamond player, I must maintain my elo every 28 days to keep my rewards, why don't gold players have to? And as I stated, this isn't an anti-gold post, the better question is outside of masters/challenger, why does anyone have to face decay?

My only theory is to catch boosted players. For example, every 20-25 days when you have a diamond 5 0 LP player gojng 0/15, it's a pretty good indicator that this player was boosted. But that's such an inefficient method of preventing boosting since:

A) most boosters will play a game for them every 20-25 days to prevent decay and suspicion.

B) Most boosts take place at the end of the season to avoid this all together.

So at this point, you only have this to catch, what? Maybe 0.5% of a player base that is boosted and stick it to the rest of the legit players for a system that isn't efficient anyway? And lyte has already mentioned working on a system to actively catch boosted players/boosts, so clearly he realizes this method isn't efficient either.

Also, the other incredibly stupid part about this is that your LP decays but your MMR does not decay. For example, I have a friend who has to go away for 2 months for on-the job training where he's not able to take any computers/laptops outside of company sponsored ones for online testing that don't allow him to add anything onto it. What if he was diamond? By the time he'd get back, he'd decay down to low plat but when he continues his ranked play, he'd be low plat PLAYING AGAINST DIAMOND PLAYERS. Sure, he'd gain more LP and likely skip divisions but why is he even faced with such a daunting prospect in the first place? To prevent people from purposely decaying to bronze, again, an extremely tiny population that pales in comparison to the legit players this negatively impacts.

Outside of catching boosters and the LP decay/non MMR decay catching a small amount of abusers, I can't possibly see why you'd have elo decay. Because if your reasoning is that you must maintain your climb/rank to receive rewards, then you're admitting that getting gold isn't hard OR your entire reason is contradicted then by saying you don't want people to lose them once they obtain them, thus the reason for not decaying in gold. Once again, this is not an anti-gold rewards post, but any reasoning you present for gold not decaying makes absolutely no sense and is contradicted completely. And my solution to that isn't to stick it to gold players, it's to remove decay entirely outside of masters/challenge and perfect your elo boosting detection system.