No, it definitely did not always cost $2k a month.
B) Biden papered over A) with "temporary" covid subsidies in 2021 and those are going away, revealing A) again
The underlying issue is inflation adjusted healthcare related spending increased 6x per person since 1970. Some of that is an increase in quality, but middleman are a huge factor.
Unsubsidized bronze plans were in the $250-350 range in 2016/2017. That's nowhere near rent.