The grappling techniques in modern MMA is a mixed bag, not just GJJ/BJJ. Wrestling has also played a tremendous factor in shaping "MMA Grappling" as well. That varies from school to schools and system to system. I've studied traditional striking systems that taught takedown/grappling defenses as well as other systems that didn't. Traditional striking is a very broad category and is too diverse in methodologies to say none of them teach anti-grappling. There's without a doubt some delusional practitioners who believe that(I've met some of them), but there's also many traditional practitioners that take anti-grappling seriously. They put a lot of time and effort in developing anti-grappling skills and are capable of defending takedowns.