While I don't believe there is any link. I've always found it strange that the US bundles SO many vaccines together in a shorter period of time compared to NZ/AU/UK.
AFAIU, combined vaccines are preferred in the U.S. because we have problems with compliance, scheduling, and follow-up, especially in at-risk communities. Minimizing the number of appointments this way is a simple technological workaround to deeper sociocultural issues. Other countries may have similar problems, but the U.S. has a habit of leaning on technological solutions, for multiple reasons but in no small part because we're crazy rich and can; whereas some other countries are more predisposed to low-tech, behavioral remedies.