Two things going on here. 1) Rental rates saw big jumps during the pandemic and are giving up some of those atypical gains, and 2) a lot of large apartment complexes that were conceived and financed in the low interest rate environment are finally coming online now after the 2-3 year land acquisition-permitting-construction-lease-up period and this is causing an oversupply.
And, a lot of people moved during COVID. A lot of those people realized they don't like living in states that take away people's rights and persecute LGBTQ and minorities. A significant number of people are fleeing red states for political reasons.