More accurately, earning a high college GPA and MCAT score are the first gate that pre-meds have to get through to get admitted to medical school. Then there are lots of other things beyond that…
However, at least the in-state Texas public medical schools are relatively inexpensive by medical school standards (but there is still a lot of money involved, so keeping cost down for undergraduate can help). Staying in Texas would help make them more accessible to medical school interviews.