Street Trees

I've noticed that a lot of homeowners have not removed the strap/anchors from their trees. As the trees have grown, the straps are cutting into the bark and damaging the tree. They are only intended to be in place for the first year, as the roots get established.

There are also several trees with low branches that can swat you in the face as you're walking, or with branches that obscure signage.

Should the association send a notice to homeowners to remove the straps and trim branches (leaving none lower than 5' - or 6-7' on sides facing signs)?

Or should we just hire a company to do this, since many owners would either just ignore such a notice or not have the tools/ability to do this themselves?

And to protect our trees from opportunistic infestation/infection after branch trimming, I hope some of that "black goop" could be used to seal the cuts.