Each situation is unique.
Recommend doing your own research.
Meningiomas are "typically" benign, but they can be cancerous as well.
They "take years to grow" but who knows how long that is.
Do the regular MRIs. They aren't radiation like CTs.
They don't typically "cause an issue" unless pressing on or wrapped around something (in my case, pressing on left side optic nerve, needing emergency crainiotomy;another one wrapped around right side carotid artery which I had proton therapy treatments for).
Second opinions should be done. I was not recommended for proton therapy but very grateful I did my own research and found doctors who readily accepted me for treatment. I did not want another craniotomy. Even if I get more meningiomas, I am grateful for the doctors I've had, and grateful that I did my own research.
Ask every question you have.