I have no definitive proof on Chamber sites. Years ago I wrote an article on our website "an SEO says Bye Bye to the BBB" as the BBB changed their outbound linking to nofollow instead of dofollow. Aside from the link, you got the logo on your site, which used to be a big deal for certain businesses where their clientele looked for such things, but those days are behind us for the most part too.
The Chamber sites I treat in the same manner. There is an advantage if they link to your site as it's a local organization linking to you. We all know how hard it can be to get local-type links. But, on the other hand, they are very much a "pay to play" type organization.
If you're actively involved in the chamber, then by all means, grab a link. I wouldn't spend $650/year on it though as you could just as easily put $650 into Google Ads or Facebook and should be able to pick up some leads.
We have some clients that have their local chamber, others that don't, there's no heavy weight assigned to the link.
Again, no definitive proof on this, just what I've observed over the past 20 years.