Crawlspace Humidity at 90%: Should I Act If There’s No Mold?

I recently bought a house that was built in the 90s and I've been monitoring the humidity in the crawlspace with my hygrometer, which consistently reads over 90%. I've had three different crawlspace professionals come out to assess the situation. One suggested a full encapsulation along with a french drain for around $20,000, while another just recommended a dehumidifier. The third proposed sealing the vents tighter, closing off the area under the porch, and installing a dehumidifier as well. The thing is, there's no mold present at all. Given that the previous homeowner might have done some remediation, is it reasonable to hold off on any drastic actions and just keep an eye on it for potential mold growth? There is a vapor barrier installed already.