Off the top of my head:
Rav JBS, in his 13 addresses, said “the more one can distance one’s self from secular culture the better one is for doing so…” and that the reason for creating this new MO movement was that he (incorrectly) feared that traditional Orthodoxy would become a museum piece and couldn’t exist in the new America. B”H, this did not happen.
Therefore, it is quite clear that Rav JBS himself felt that MO was NOT lichatchila in any way.
So since Traditional Orthodoxy CAN and does, B”H, not only exist but even thrive, in this (not anymore so) new America, there is no valid reason to “modernize” Judaism when doing so is at best a bidieved according to Rav JBS, its founder.
Does that help?