Don’t you have the same issue with any query optimized product? If I’m using redshift and hit a bad execution plan that I can’t get around by tweaking the query I’m SOL, and redshift engineers aren’t going to tweak a configuration change to help me.
This is why products like DynamoDB were created - cost based optimizers are imperfect and unpredictable, and once you’ve stepped over some limit or threshold performance wildly changes. The reasons can be your query, or the data has changed, or there’s a noisy neighbor consuming a resource you depend on for your query. If you need highly predictable times you can reason about you won’t get it from any RDB solution.
Given that, what about snowflake feels different? That the details are obscured from you so you don’t understand why things are happening? Is the lack of ability to deeply introspect making you uncomfortable? My experience had been the ability to introspect rarely leads to any change in outcome but instead leads to me identify the query optimizer has done something stupid I can not do anything about, but at least I can point to the specific resource being exhausted by it.