You do lose range but the question is whether that range is really useful.
I used to run 26/38 and 11-36. Bottom end was 26/36= 0.72; top end 38/11 = 3.45, total range = 479%
I now run a 32T front with a 40T extender, and when i go somewhere really hilly I swap to a 30T front.
On the 30T front the low end is now 0.75, which is pretty similar to the original bottom and certainly useable for what i can manage. The top end is 30/11 = 2.72 which is way less than before. Total range is 363%
But – on 30:11 at say 100rpm, which is spinnable for a prolonged period, on a 29er, that equates roughly to 39 km/h. Which is plenty fast enough, and if I’m hitting that speed off road it’s not the gearing that bothers me, it’s my bottle / brakes.
YMMV