No realistic slope simulation while riding

Hello Zwiftpeople. I have only recently started using Zwift and I have already had some fun with it but I have the feeling that my trainer or zwift do not have a realistic slope simulation while climbing.
I have a smart trainer (Elite Suito) that should be able to simulate gradients up to 15% but when I start climbing I would expect I have to shift down and I would really feel like I am starting to climb.
But the only thing I see/notice is the speed dropping down. I can actually just stay on the outer blade to climb. I just have to push harder and produce more watts to increase speed. Like in ERG mode but I don’t use that mode in grouprides. All my sensors between the smarttrainer and the zwift app are also linked and paired correctly. I have even set my ‘trainer difficulty’ to max to have the maximum and most realistic climbing experience, but so far I don’t think it’s really realistic climbing? Is that normal or is there something wrong with my setup? I use a laptop and bluetooth connection… Hope you guys can help me out?

Have you paired the controllable device as well as the power device? If you’re using ANT+ then make sure you’re using the FE-C device in that controllable pairing.