Luckily the House of representatives have set up the rules such that they can call to change their majority leader whenever they disagree with each other, so very few actual policies will change.

A bunch of things did get changed during the last presidency because of the Republican majority.

Healthcare, internet privacy, hell even how mail got delivered.

If it’s not from policy changes, it’s from gutting the department and putting in cronies willing to sabotage the industry. You brought up environment policies, yeah those are gonna die.