Yes it would be silly to ground an aircraft that had a wing structural failure after the tail had already been torn off due to outside influences (such as overspeed after stall, or entanglement with a parachute).
We don't know what the actual failure scenario was though.
The question is whether they are grounding because (a) due to specific evidence that they suspect a structural problem, or (b) they are the type to ground something when they don't yet have any evidence either way. Wait and see.
The EASA AD is vague as to the reasons for its decision, as it says it is both following the lead of Australia's temporary grounding, and using "all available information".