Idiot. Why didn't you research metal/crystal mining efficiency?
And here is the post of someone who hasn't bothered to read any of the posts.
Disagree completely with OP for two reasons. A) Games would go on longer than they already do. Losing your fleet has to mean something. Without these upkeep costs you could crank out an entire replacement army in a matter of minutes.

It forces you to make a tough decision in upgrading your fleet size.Upkeep is good as is.
Well, it still would. However, if I take a substantial loss (lets say 1000 fleet worth of ships get hit by advent who have rank 3 malice...yeah, that ability is beyond crap if the fleet is cluttered...anyways) and wipes out my fleet really fast, regardless of anything I can do (With malice active, you can lose a clustered fleet within 30 seconds, and a slightly spread out one in only a slightly larger amount of time) my fleet is crippled. Theoretically, I still have another 1000 fleet cap worth of ships somewhere else to help hold off the enemy, but what happens is that I still have a 75% upkeep cost with only 36.5% of the fleet cap being used.
If this happens, though the fleet upkeep should NOT jump down to 36.5, (nor should it instantly adjust in any fashion) it should, however, start to slowly trickle down to something else, such as going from 75% to 45% over the course of a few minutes.
In real life, though the logistical supply lines may not stop instantly, they still would be ramped back if they were no longer necessary. Regardless of if the military can support a larger amount, they don't need it, so they spend less, and as such produce less.
Now, what can be done is, as it goes down to 45% (again, it would never be one to one, some units would ALWAYS be left over, regardless of logistical necessity), it can also reduce maximum fleet cap, until it is, say, within 200 of what you currently have (so you can still build).
Then, as you build more, the supply lines are slowly re-engaged, upkeep slowly scales up, and available fleet cap slowly increases.
This way, if you suffer a massive defeat (regardless of if you were being an idiot or not, and regardless of your economic prowess), the upkeep will slowly scale back, and when you start to rebuild, it will slowly open back up. This way, nothing is instant, and it takes *time* for it to take effect, but it is still significantly less punishing than having 75% upkeep with only 30% actual worth of fleet remaining.
Sure, it should be a choice to get that tech, and the tech should not be un-researchable. It should still somewhat punish you if you take it when you aren't ready. However, if you take it when you are, and are just crushed because you got outplayed (or got hit by the insanity that is Malice, which really is overpowered, try it yourself) and maybe had some infrastructure destroyed in the process, you should not have a choice you made that was viable absolutely and completely crush any chance you have of future success.