Was that executive power really accrued as a result of a resistance to Trump during his first term? My understanding is that the executive branch has been exerting more power for while now, regardless of who has been in office.
And does it really matter? The authority for doing many of the things Trump's current admin is doing don't actually fall to the executive branch; they're doing them anyway.
Well it's more initially as a response to the internet (as an uncontrolled media landscape) and so-called "hybrid warfare" -- but it was deployed against trump, and increasingly so-called "far-right populism" against which it was "necessary" to deploy the full resources of the executive to "preserve democracy" (claims I don't entirely disagree with, but tactics which are nevertheless unconstitutional).
Consider that Wikipedia lists the Biden connection to ukraine as a "conspiracy theory" but the trump connection to Russia as "Links between Trump associates and Russian officials" (there is no Trump connection to Russia, this was an invention of the security services; and there are as many "Links" between Biden associates and Ukraine -- but, as with trump, there is no Joe Biden-Ukraine link).
And does it really matter? The authority for doing many of the things Trump's current admin is doing don't actually fall to the executive branch; they're doing them anyway.