It appears that Amazon/Alexa API added some features to allow utterances for open/close instead of on/off for devices like window blinds/shades or Garage Doors
Hubitat hasn't added this to their Alexa skill yet, but it's possible to create your own skill as a bandaid in the meantime. I did it to control my blinds, and posted here:
I am in fact using your driver for my iBlinds and that is working really well. Thanks for that! I am not sure if I can get through the process for the band aid you have made to allow the open/close function. It seems beyond my level...How does one “Nudge” the actual Hubitat Devs on here to make things like this happen? Seems like the community is too big now for them to see every discussion or topic.
I've posted it in the Feature Requests topics. I know they have a large backlog of things they'd like to do, so I'll just have to be patient. But I am a little impatient, which is why I made my own skill.