where did you get that number from?!!! It reminds me of all the paranoia I experienced, years ago when I purchased my Gen 2 Prius. We have all seen how that ended with very long battery life and pretty inexpensive replacement. And the gen 5 battery looks very serviceable, something I would probably tackle myself, other than recharging the refrigerant.
The entire traction battery needs replacing if there's a refrigerant leak. OK, maybe around $10,000 instead of $20,000. LOL Hybrid system Malfunction (Visit Your Dealership) | Page 4 | PriusChat
It's important to remember that this isn't Toyota being honest about what's possible for repairs, just that they are trying to convince everyone that all the AC components and HV battery components are integrated and have to be replaced as a single unit. Truth is Toyota said the same BS about repairing hybrid batteries when a cell goes bad, but a quarter century later there's hundreds of successful businesses doing just that, most notable GreenBean/LKQ, GreenTec, Hybrid2Go, PriusKings... As in Toyota is more interested in defrauding their customer with outrageous repair prices than telling the truth about how to fix something in an affordable way. This is one day going to blowback on them in spectacular ways. You can only rip people off for so long before they lawyer up and start fighting back!
To be fair; Toyota doesn't overhaul motors or transmissions either. They are assembly/parts replacement jockeys. It takes a lot of time and equipment to "properly" repair a traction pack. So at $200+/hr recharge rate; it's cheaper to replace the entire pack, than to fuss with it. You also failed to mention the amount of come-back/warranty repair and high failure rates of those "slapped together" packs. Toyota doesn't want their name associated with refurbished packs that just last a few more years - and I don't blame them. Toyota sends your return "core" packs for professional refurbishment; which means ALL new battery modules. Something they can warranty and stand behind. Dealerships operating cost are high; unlike a small business that's allowed to cut corners and only employing one or two people. Believe what you will - It's a free country; for now......