I am sure others can add to this but a few differences:
Viya for Learners is currently using Viya 3.5, commercial release is Viya 4.0. We are working on upgrading to Viya 4.0. https://communities.sas.com/t5/SAS-Global-Forum-Proceedings/SAS-Viya-3-5-and-SAS-Viya-4-A-Side-by-Si...
There are a few release changes… we are currently using Visual Analytics 8.5. you can check out the documentation to see the differences in the application over the update releases.
https://www.youtube.com/watch?v=RsVDbHnsFXQ
https://documentation.sas.com/doc/en/vacdc/v_023/vawn/titlepage.htm?fromDefault=
Viya for Learners is for ‘learning’ not research or business use so we have a file upload limit of 100MB and total upload storage limit is 5GB.
Viya for Leaners is a multi-tenant environment, which means everyone logs in and gets assigned a tenant (machine), that is your machine and you can save stuff to your folders but sharing reports requires a little work https://communities.sas.com/t5/SAS-Communities-Library/Sharing-Reports-in-SAS-Viya-for-Learners/ta-p...
As far as missing features…
-auto tune is turned off for building models
-custom shapefiles/polygons are not enabled
Those are the two off the top of my head. Again, others will add to this.