The 23rd Amendment gives DC 3 electoral votes, even though it has no senators or reps. In giving DC statehood, they get 2 senators, and one rep. Not really a great deal when you consider that admitting, say... Puerto Rico, would give them not only 2 senators, but probably at least 3 reps, and 5 EVs in addition to the ones from DC, which are already safe blue anyways.
Bearing this in mind, why are they pushing for statehood for DC specifically? If it was just about padding their numbers, and consolidating power, then why not go for PR, or even Guam?
I have never had much of an opinion one way or another on the Corporation of the United States theory, but the above makes me think maybe there is something to it.
You're missing a key detail in number of electoral votes. Under the current Constitution, DC can have as many electoral votes as it would have if it were a state, BUT it can not have more electoral votes than any other state. So because Alaska and Wyoming only have 3 electoral votes (due to their smaller populations) which btw is the minimum any state can have, DC is limited to 3 electoral votes.
If DC became a state, its population would justify giving it more than 3 electoral votes.