Unlike boy groups, is it truly difficult for small-agency girl groups to target the global market?

‌There is the BTS case, of course. But it seems to be common knowledge in this industry that boy group and girl group markets are very difficult to group together, so hmm...
Representative cases of small-agency groups succeeding are Secret and GFRIEND; even if we set the former aside since it was the early stages of global expansion, people usually cite GFRIEND as a prime example.
However, in my personal opinion, the reason GFRIEND couldn't expand beyond Asia wasn't due to their small agency, but rather because their early "school concept" was a fatal flaw.
I forget which program it was, but there was a broadcast where female singers went to perform for a gathering of both the ROK Army and the USFK (US Forces Korea). When a female soloist first appeared, both sides of the soldiers cheered like crazy, but when GFRIEND came out second or third, while the ROK Army showed the same frantic enthusiasm, the reaction of the US soldiers watching the ROK Army was... oh man, seriously...
As I write this, I find myself leaning toward the GFRIEND side ^^;
If they insist on easy-listening, I believe RESCENE will also find it difficult to target the global market. If they transplant the colors of the 2nd or 3rd generation "pretty girl" style as their dual wings, I think the possibility will increase quite a bit.
These are strictly my personal thoughts. That's all for now~