No, it is quite deliberate, though I am sure it is going to be tweaked further.  Quite a few tech were radically increased in base cost, presumably as both a brake on rapid tech expansion and as encouragement to build more research plants.  Before 1.2 there was little reason to build many research facilities, at least compared to GC II.  Presumably this is being done to force players to spend more time on research. After all, the way to get those tech quicker us to build more research plants.

Orbitial Manufacturing and Large Hull Construction also got massive increases in tech cost.  Probably many others as well.

I suspect you'll find the other two DO cost a lot more once you reach them, actually... but yes, the changes are being reviewed, not least because the AI cannot cope with these costs presently and may spend several hundred turns attempting to pick up ZGC.

I like the new system better too.  All of us generally try to get large hulls as soon as possible and this helps put the brakes on.  Once you're over the hump, the techs downstream get easier to research.

There are other key techs that cost much more as well.  I think it makes it more interesting.

I have read through the posts and I can see the value of the higher hull build costs.  That said, the communication around the somewhat massive shift in research costs wasn't highlighted anywhere.  For a regular casual player, revisiting the change after the 1.2 update felt like a total bug.  I'm going to hunt for the release notes to see if I skipped over it. 

In my most recent game the Dregin had medium hulls within the first 100 turns and when I went to match them, my cost was 60 turns to research the same thing.  Hence, my thinking it was a dev error.  Thanks for the feedback on this thread too - GalCiv has a great community. 

I also noticed this in my latest game. Fact is: Some AI races do have this in turn 120 or so. I play on gifted, which means the AI tends to pick on me early, and to even the odds I had to pay a minor race an arm and a leg (i.e. all my techs plus all my money) to get it. But now its payback time. While I find medium hulls to be a key technology, and I like one has to work to get it, I still think the costs should be turned down again somewhat.

I would love the dev team to post something about the recent balance pass on the research trees with their view on the matter.  STS80 has a great point about the defensive techs still being the same - I've seen a similar approach to the AI building ships and getting stuck on single techs. 

I started a new game with the Terran's and focused on several specialized research planets to the exclusion of production and the economy, moved the governer slider almost entirely to research and even with that, I found the medium hull price at about 35 turns.  I totally understand the change, but feel the pendulum has swung too far the other way.  A post from the devs would be helpful at this point (I think).