As Style mentioned. Toyota did indeed design and define the car as a tourer.
However, that doesn't mean it's got to be defined as a hauling sluggish motor vehicle.
The fan base has turned the car into something much more. But by definition, it's a GT, touring 3 door. However much you stomp lol.
Regarding the torque difference, NA is 10.0:1. Various sources to hand state 9.2:1 is an NA engine with a TT headgasket.
I'd just like to add that TT owners don't complain about the low-end drop in performance, and they have a 8.5:1 ratio so will see worst low-end response.
There is some data on thermal efficiency when considering engine engines with Otto cycle. https://www.ohio.edu/mechanical/thermo/Intro/Chapt.1_6/Chapter3d.html
Feel free to research
To generalise, you can find data online that indicates a rough amount of power loss for the lower compression ratio. Remember, however, this value is below 3.8k before the turbo spools. Once that turbo begins to introduce a pressure change you are above and beyond the NA.
I've spent time looking into this, understanding the maths and I believe strongly there's going to be a 5-10% loss in torque at the most, in sub 4k rpm values. Looking at the stock dyno curve, that's maybe 20 ft lb.
Honestly. If this bothers you, buy a torqamp electric charger pre-turbo. Gives 200 ft lb at sub 4k rpm. I'm considering it for lower end power. But not, to replace what my compression ratio has lost. That's really peanuts.
I find it highly unlikely you'll be able to notice it. Your lower end power felt as a percentage, more responsive. It was around 50-60% of your total power. Now, its 30-40% if not less. So that part of your power band is going to feel less by comparison.
The car will, of course, feel slower lower down, because the overall performance power band is not the same distribution of power it once was. It's been increased at the top end not the bottom.
You need to honestly get over this compression stuff mate. It's not an issue. Wanting lower down performance is a separate issue that we all want, but chasing the compression ratio you have lost isn't the way to get this. You haven't lost anything worth worrying about low end.