If demand is projected continue for a long time, this may encourage more competitors to enter this space, so supply will increase.
On the other hand if everyone thought that the demand will end soon, nobody would invest in more capacity and shortage would last longer.
I think this is just for short term shareholder profit.
Competitors are going to come online anyway because of the threat of chip embargoes against China that mean they are investing in production regardless of what the outside world is doing.
There are no competitors that can muster the capital to make decent RAM... other than China but China is under a heavy sanctions and tariffs regime, when Apple mentioned using Chinese RAM to ease pricing they were quickly shushed by above.
The current monopolists aren't building new capacity either or are simply pretending to do it. It's a planned monopoly market for reasons I can only speculate about.