Because you can research no more than 1 tech a month, that "zoom through the tech" argument doesn't hold value.
There are at least 8 (molecular/robot, mining, generator, tech, alloy, cg, dimensional replicator, aspis) buildings which you want to maximize building. How long is that going to take? Assuming your argument isn't "just play KoTG" (side note: when is that getting nerfed?), there is no way to make these buildings viable going wide.
Further consider: each tech researched is another repeatable not researched. This setup (uncapped buildings) makes tech automation impossible in the late game. At least a planetary build cap would have a reasonable end, but this would just mean a Cosmo empire in endgame who didn't go through the tedium of clicking a tech every single time (and how many options will we have to browse through now?) will be considerably weaker than others.
I don't know, this just seems like the worst way to go about solving a problem which frankly doesn't even seem to exist. Like someone mentioned earlier, if they think it's too strong in MP have the players agree not to take it. I know a lot of people already consider it inferior to other crisis in MP because of how long it takes to come online, and the questionable relative value of riddle escorts.
I think before any of this debating goes on the question has to be answered: what problem is this change solving? Because it's certainly creating a lot.