I saw the writing on the wall 2 years ago - SmartThings was going to end Groovy SmartApps without first having a clear, complete, local platform for automations. At the time, the WAF for all automations I had using SmartThings was terrible - she hated that everything was unreliable or randomly delayed.
As a result, with my new kitchen (Recommendations for kitchen remodeling (2020)), I went with Hubitat. The advantage is an all local, reliable automation platform. The WAF in our household has gone from “no way” to “can you make the pantry lights go on when I open the door?”.
Home Assistent will likely give you a similar result (reliable, local).
Clarification: it’s 2 years later and SmartThings still doesn’t have a clear, complete, local platform for automations. Nor are Edge device handlers out of their extended “beta”.