Good question indeed. From what I've gathered thus far-
"The La Palma site where TMT is being re-proposed is not vacant. It is the sacred mountain of the Benahoaritas, the last indigenous Guanches (an ancient Berber people who were there for thousands of years), who were almost wiped out, but from whom many of the island's living people are descended. The mountain is the site of the last standoff against Spain, the same year that Columbus was making trouble in North America. Some are active, and do not want TMT either. Letʻs be clear: it is not enough to remove this project from Mauna Kea and build it on someone else's sacred land. Astronomy needs to EVOLVE, and stop destroying our Earth to look at the sky, period."
https://www.amazon.com/Guanches-Survivors-Their-Descendants/dp/8492052759