I think the issue is less so wanting more power and more so of wanting more range. The touring with 20/21s is 100+ less miles than the GT. That is a huge difference. The going faster is nice, but the more range equals longer distance, less charging stops and even quicker charging times which makes all of the difference in an EV. My wife doesn't need the power, so I was going to sell her on the touring, but for the price delta, I'd rather us swing up to the GT for all the benefits of the added range since this will be our roadtrip vehicle. My feelings is "if your budget tops out at the Touring, then do it. If you can swing it, the GT makes more sense."
I'd say though this, if anything, shows how good the GT is and has become the baseline of comparison. Compared to a GT, the Touring is not seeming like such a good deal. Compared to anything else at this price point, the Touring is actually a strong offering. I do think it will sell more than the GT as you suggested, but I can also see people considering the Touring initially but going up to the GT for the additional range if their budget allows. I know it seems silly to think about value on an $100k+ car, but it matters as well and that is what I think Lucid is thinking about here too.