I've seen some adjustable earplugs like the Loop Switch but they start at 15dB which is too high. There was the Knops which started at 0 which was great but they don't seem to be available anymore and their website is gone. They were also pretty prohibitively expensive for passive earplugs.
I'd also love active noise cancelling plugs that could eliminate background noise and make voices more intelligible. Like when you're trying to speak on a noisy street or in a nightclub. But I don't think the tech is there yet.
If anyone knows a comparable product to the Knops that are still available I'd be interested. I've been looking all over.
Just some links to show what I mean:
Knops: https://www.theverge.com/circuitbreaker/2017/4/19/15360206/k...
Loop Switch: https://www.loopearplugs.com/products/switch