Your theory that Republicans swallow anything put out by self-styled "conservative" think tanks like manna from heaven isn't born out by the facts, is it?
Actually, it is born out by the facts.
The individual mandate was proposed by the right wing Heritage Foundation in 1989:
Assuring Affordable Health Care for All Americans.
Mandate all households to obtain adequate insurance. Many states now require passengers in automobiles to wear seatbelts for their own protection. Many others require anybody driving a car to have li a bility insurance. But neither the federal government nor any state requires all households to protect themselves from the potentially catastrophic costs of a serious accident or illness. Under the Heritage plan, there would be such a requirement.
We then see Republicans swallowed the manna and see the individual mandate proposed by the Senate Republicans as an alternative to HillaryCare in 1993:
Health Equity and Access Reform Today Act of 1993
INDIVIDUAL MANDATE- The Secretary shall specifically make recommendations under paragraph (1) regarding establishing a requirement that all eligible individuals obtain health coverage through enrollment with a qualified health plan.
In 2007, Senator Ron Wyden, Democrat from Oregon, introduced the
Healthy Americans Act, which was co-sponsored by 20 Republicans and contained an individual mandate.