Ever since damage values have been removed, I've been looking for any bug report, video, or something to say that this is a problem. The explode data for TNT was removed since then. The only means of acquiring TNT of this type is through damage values only. In the debug menu, "explode" appears, but doesn't classify as data or a blockstate (1.12). I'm not sure if this is an actual issue, or if this will be resolved as "Works as intended", but it's still worth displaying somewhere.