Drones are not there to take over for humans, drone-based weapons are ridiculously effective compared with anything before them and there's plenty of space for more computing power to make them even more effective.
Actually, this is the main reason why drones will be needing more and more compute; to ensure that they can be as autonomous as possible.
Whether they will be able to reach or surpass humans in this regard is still disputed by some, especially those who think that the human brain is powered by some kind of non-material soul.
> human solders act as a political tripwire
This really only applies before a war starts. Once it has started, you want to have the best equipment you can within your budget.
Now there are other political reasons why autonomous drones may be resisted, primarily that they can be seen as very scary or even evil by onlookers. But the same could be seen by current remotely piloted drones, but that hasn't stopped the US from frequently using them for assassinations at least since Obama's period.
Once drones become able to operate without a human to control them remotely, they will. Especially if jamming limits their ability to communicate.
Human soldiers can be killed. If e.g. Russia bombed a US military base in <country>, then the US has an instant cassus belli (and is politically forced to respond drastically and be drawn into the war) and <country> knows this, which makes the US military base a far more effective red line against Russia as a result. In other words, human solders act as a political tripwire that more effectively binds allies together.