He was a luxury they could afford while they had the significantly fastest car, but now things have leveled off he will cost them the constructors if they aren't careful.
If rumours are to be believed they turned down Lewis, Fernando and Carlos to resign Checo. I wonder what would cause them to keep a clear number two driver?
I doubt Lewis wanted to go anywhere but Ferrari. Especially with Newey heading there. And as for Carlos, zero chance Jos would have allowed that. For better or (mostly) worse, Max and Jos seem to have outsized influence at Red Bull.