I totally understand if Databricks doesn't fit your use cases.
But you are doing a disingenuous comparison here because one can keep a "serverful" cluster up without shutting it down, and in that case, you'd never need to wait for anything to boot up. If you shut down your EC2 instances, it will also take time to boot up. Alternatively, you can use the (relatively new) serverless offering from them that gets you compute resources in seconds.
To ensure I'm not speaking incorrectly (as I was going from memory), I grep'ed my several years' of databricks notes. Oh boy.. the memories came flooding back!
We had 8 data engineers onboarding the org to databricks, it was only after 2 solid years before they got to working on serverless (it was because users complained of user unfriendliness of 'nodes', and managers of cost). But then, there were problems. A common pattern through my grep of slack convos is "I'm having this esoteric error where X doesn't work on serverless databricks, can you help".. a bunch of back and forth (sometimes over days) and screenshots followed by "oh, unfortunately, serverless doesn't support X".
Another interesting note is someone compared serverless databricks to bigquery, and bigquery was 3x faster without the databricks-specific cruft (all bigquery needs is an authenticated user and a sql query).
Databricks isn't useless. It's just a swiss army knife that doesn't do anything well, except sales, and may improve the workflows for the least advanced data analysts/scientists at the expense of everyone else.
This matches my experiences as well. Databricks is great if 1. your data is actually big (processing 10s/100s of terabytes daily), and 2. you don't care about money.
But you are doing a disingenuous comparison here because one can keep a "serverful" cluster up without shutting it down, and in that case, you'd never need to wait for anything to boot up. If you shut down your EC2 instances, it will also take time to boot up. Alternatively, you can use the (relatively new) serverless offering from them that gets you compute resources in seconds.