$4,000 to $10,000 for a single tree removal is incredibly high. In a very high cost of living area I can have a very large tree removed by a licensed insured removal company, the best in the area, for $1,500.
Are you in the Bay Area? NYC? Those are about the only places I could imagine paying $4k or more.
I suspect over the pandemic and lumber boom, a lot of qualified/insured/bonded arborists ended up getting forestry jobs and in-city arborists became scarce, temporarily anyway. Kinda like what happened to shipping container prices.
Are you in the Bay Area? NYC? Those are about the only places I could imagine paying $4k or more.