People shouldn't be too discouraged by this saying that it's only for contact negotiations. A very similar situation was there for Kroos in 2014.
Bayern signed Gotze the season before and he was on a lot of money, Kroos had one year left and during contract negotiations wanted to be on the same payroll as Gotze. Gotze came off a decent but not amazing season so there was validity for Kroos wanting as much money given he was with Bayern for longer and had better performances. In the end Bayern didn't want to pay him that much and were forced to sell him to Madrid for a very low fee.
Jump to 2021, Bayern signed Sane the season before and is on a lot of money (300k per week rumoured). Goretzka has one year left on his contract and wants to be atleast on the same payroll as Sane. Sane has come of a disappointing season so there is validity for Goretzka wanting as much given he's been with Bayern for longer and has had much better performances. If Bayern can't agree a deal for Goretzka, like they didn't for Kroos, they would be forced to sell him for a low fee.
The potential differences between then and now is:
1) Bayern already had Thiago, who was very highly rated and similar to Kroos, so a replacement wasn't an issue. Bayern right now don't have a highly rated replacement for Goretzka and would need to go to the market to get one. Given they are cash strapped due to Covid, it would be difficult for them to buy a star with Goretzkas potential.
2) Neither the Bayern board nor the fans really rated Kroos then (sadly). Thiago and Gotze were considered better prospects and therefore people though Kroos was going above his ability when he asked for as much money as Gotze. Therefore they were more willing to let Kroos go. Goretzka though is really highly rated by both the management and fans and therefore they would be more willing to give him what he wants, rumours though say they have doubts over his injury record and therefore don't want to give him a lot of money.
Obviously not 100% the same as the Kroos situation, but definitely hope that Bayern would be forced to sell if they can't agree to a new deal.