Before everyone starts jumping to conclusions I just want to start by saying Desantis is a toxic douche who I do not and will never support. Please hear me out though.
The worst thing about federal agencies is that the President can control them with Executive Orders. In other words, power granted to these agencies is power granted to whomever the President is.
Getting rid of them does mean that we lose many regulations in the short term but it gives the power back to Congress and the states (yeah I know some states are going to do stupid shit and Congress is going to sit around with their thumbs up their asses and take forever to enact policy to replace it).
Long term getting rid of federal agencies could actually help protect us should another tyrannical President be elected.
If you want an example of why executive power is dangerous just look at what Trump and Ajit Pai did to internet regulation after the FCC was given control of the internet in the name of net neutrality.