I can think of reasons why Democrats would not like this.
Currently the Democrats can count on 55 electoral votes for president from California. Under this plan, I’m not sure they can count on all three new states automatically voting Democrat.
Based on the map it looks like libs would control the new northern state and the coastal state. How is this a win for anybody but the rats.
I can’t see the powers that be in CA allowing this. Yes, more Senator’s but the only reason a Dem has a shot at the presidency is due to the automatic 55 electoral college votes from CA. They get almost 1/5 of the needed votes without even trying. This would break things up enough so that they’d have to at least fight for all of those EC votes - moving funds away from other battlegrounds. It would only take a part of them to vote Republican to make it virtually impossible to have a Dem POTUS.