Simply increasing processing power for the AI isn't enough. Gameplay mechanics are intimately related to the capabilities of the AI.
For example, when they redesigned combat around the 1-Unit-Per-Tile (1UPT) mechanic for CIV 5, this crippled the ability of the AI to wage war. That's because even if a high-difficulty AI could out-produce the player in terms of military, they were logistics-limited in their ability to get those units to the front because of 1UPT. That means that the AI can't threaten a player militarily, and thus loses it's main lever in terms of it's ability to be "difficult."
Contrast this to Civ 4, where high-difficulty AIs were capable of completely overwhelming a player that didn't take them seriously. You couldn't just sit there and tech-up and use a small number of advanced units to fend off an invasion from a much larger and more aggressive neighbor. This was especially the case if you played against advanced fan-created AIs.
I'm hoping they get rid of 1UPT completely for Civ 7, but I have a feeling that it is unlikely because casual players (the majority purchaser for Civ) actually like that 1UPT effectively removes tactical combat from the game.
For example, when they redesigned combat around the 1-Unit-Per-Tile (1UPT) mechanic for CIV 5, this crippled the ability of the AI to wage war. That's because even if a high-difficulty AI could out-produce the player in terms of military, they were logistics-limited in their ability to get those units to the front because of 1UPT. That means that the AI can't threaten a player militarily, and thus loses it's main lever in terms of it's ability to be "difficult."
Contrast this to Civ 4, where high-difficulty AIs were capable of completely overwhelming a player that didn't take them seriously. You couldn't just sit there and tech-up and use a small number of advanced units to fend off an invasion from a much larger and more aggressive neighbor. This was especially the case if you played against advanced fan-created AIs.
I'm hoping they get rid of 1UPT completely for Civ 7, but I have a feeling that it is unlikely because casual players (the majority purchaser for Civ) actually like that 1UPT effectively removes tactical combat from the game.