Yes, but the inputs to jq are not JSON, they are "a sequence of whitespace-separated JSON values which are passed through the provided filter one at a time" which is the relevant thing if you are going to try to replace jq.
Yep, kind of.
The comma operations means that the "filters" are duplicated, so instead of one json state you would pass two if there's one coma; and ofcourse any number of commas are allowed.