I get the point about moving code around, I guess it can be problematic with some tools. In my experience PyCharm gets it right, and when moving around code in vim I can just change the indent level on the whole block at once, but it is dangerous to miss a line at the end and move it by mistake one level up.

Also I feel like changing the indent of the cursor (manually) when exiting a block is more or less the same work as typing }, and I got used to it to the point it becomes automatic.

But I guess at the end of the day it's a matter of priority. Is that more important than having special syntax for dicts? I really like the fact that we have the tuple/list/dict distinction, and would be great if we had a different paren type for sets (which would have eliminated the {} vs set() issue). On the other hand, going with begin..end or if..fi blocks would be even more antagonizing than using whitespace.