Sm has had notorious history of 'killing' older groups when they debut the new one

Sure because SNSD was sidelined after fx or red velvet was sidelined after aespa.

If Aespa is how they treat their newest group, how can we tell the difference?

SNSD is their girly or feminine sexy GG
F (x) is their Girl Crush
in the 2nd Gen
while

pure coincidence or bad timing for 3rd and 4th Gen GG

Red Velvet competition is two top GG in KPOP history
TWICE and BP

and this time AESPA their Kwangya concept + visual
look like not against the current top GG of the 4th Gen IVE and Newjeans

they had no answer to the current KPOP landscape

rather than makeover or switch concept their old GG

it easier to debut a new one
with a fresh new identity and younger idol

with snsd that was imposible, maybe all their groups were shielded and then suddenly not. So that is a little bit weird.

And they didn`t kill F(x)...they nuke them . Same with Jessica, she said she was banned to go to many Music Shows by SM. And they realy try with RV, Irene scandal, but then they had to play nice since Wendy`s accident, their image would go down if they didn`t take care of her.

They shouldn't be debuting so many groups in the first place btw, it's obv the management is ass, having more groups right now won't fix anything

What happened to SNSD in 2014 had nothing to do with Red Velvet or even SM. The media industry was truly out for them down by releasing dating news for almost every member and looking for any scandal they can find.

But you're right SM does tend to put less effort as a girl groups get older, especially after the seventh year contract renewal. Afterwards the members need to push extra hard for what they want else they'll be gradually pushed to the back.

The real history is with fans thinking their faves will disappear when SM debuts a new group. Red Velvet fans did this with Aespa, f(x) fans did this with Red Velvet; hell, going way back, H.O.T. fans were scared that when Shinhwa debuted they'd put H.O.T. on the sidelines! SM fans worry because of f(x), but really most of these scandals probably have nothing to do with the rookies. Or are we going the conspiracy route and saying SM plans these to get their old groups out of the way? I just don't find that believable, to be honest.

As a Reveluv, I don't think that SM is trying to kill Red Velvet at all for aespa. They are still well-promoted but they truly did that in the past with some of their senior groups.

It is usually not immediately after the new group debuts.

RV was going ok but not great for about 2 years, then something happened with snsd or fx, and SM went all in with RV and from that point onwards they charted #1.