Up : meta requests for a simple node is not 10 x slower, but 100x slower (2sec vs 20 msec) 
Issue created on the (inactive) overpass repo Adding the `meta` option to a simple node request makes x10 in response time · Issue #785 · drolbr/Overpass-API · GitHub
Up : got an answer. Fix is possible, but not published as “official”, on a fork.