There are regulations but the regulations haven’t been updated since the halogen bulb era. Tests designed for headlights with a single light source can be gamed by led headlight manufacturers to get approval for lamps that are way brighter than the law ever intended. Additionally, the regulations we have aren’t enforced after the design is approved. Manufacturers have to get approval of new designs but no one ever gets a ticket for blindingly bright lights. Lifting your truck or adding extra high wheels requires adjusting the angle of the headlights, but no one ever does that.

Edit: this article talks about it a bit more https://www.cbtnews.com/modern-headlights-too-bright-and-dangerous/