I'd like to note that solving the immortality problem is necessary but, not sufficient, to solve the blobbing issue in games. You need immortality, near omniscience, imagine playing Paradox games without the ledger, time freezing, a league of other gods, and infinite redos.
You can't "solve" the immortality problem, though, since solving this would involve killing the player. The only way you can really resolve this is to make this a core aspect of the game: Instead of "history, as directed by humans", "history, as directed if the King were actually an immortal vampire lord".
Removing each bonus will somewhat but not totally give the AIs more of a chance.
But that's not the problem. The AI has all those bonuses, too. The AI is also immortal. The AI also knows everything, probably more so than the human does. The problem is that the AI is stupid.
Being immortal would not help a human if they had 10 seconds to move and the AIs each did as well, scale the time up to a good number and try not to have a shit automation system.
The shit automation is an important part of blobbing. The automation is shit because the AI is shit!
Changing the player's game capabilities helps as well, although some randomness might make players rage about luck. If your empire relies on godly stats, and you lose them, and you have a time cap, adapting your playstyle to account for new stats within the time limit may not be possible and you would bleed land to rebellions or wars.
That pretty much just eliminates all of those things as viable elements of the game. If you can't depend on them, they aren't worth anything. And yet we blob anyway.
Why? Because ultimately, blobbing is the entire point of the game. Do you really think anyone plays the game for the sake of remaining exactly as they were when the game started? To precisely walk through the motions of real history exactly as things actually happened. That is not why we play these games. Sending things off the rails is the entire point. Blobbing isn't actually the problem at all. The problem is really more basic: The fact that the AI cannot keep up with the late game, because the AI is terrible at the game. Stacking super-bonii onto the AI does not make it less terrible, it just delays the blobbing while making the early game a frustrating annoyance because at that stage in the game, you don't have any pieces to play with anyway. And so the player resorts to various cheese tactics, as he must in order to survive against an opponent that is cheating as outlandishly as it does...and in the end, you still hit the blobbing stage, where the AI's advantage has now been overcome and no longer has the ability to oppose you as you paint the map.
It's all a single root cause: Shit AI.