That's just an estimate to replace everything they could think of. It's not a serious estimate to repair it.
I estimated vehicles for 30 years, any insurance company I dealt with, would have laughed, and threw that estimate away. But, the automotive side is well equipped to handle claims, and the vast majority are routine repairs.
When you have a claim on farm/construction equipment, how easy it is, is going to depend a lot on who they send out to do the damage appraisal.
Usually an insurance company doesn't have anyone on staff who can do this, so they would hire an independent appraiser, who specializes in equipment.
Sometimes, they can't get anyone to look at it, and they will try to make you do the work for them, by getting a bunch of estimates.
I would tell them you're too busy, and you intend to have it fixed at, (insert name of shop here). That's where it's going to be, and they need to get together with them, and work out the price.
There is a substantial amount of money involved in this, so I would think they will not just pay any crazy estimate, to make it all go away. but, you never know.