By selling FSD as a feature Tesla didn't expect to provide for several years, Tesla has created a unique situation, and in order to provide the purchased feature, Tesla is now providing free FSD computer upgrades and has to continue providing software updates as they move closer to providing the FSD features promised when the owners paid for FSD.
Other manufacturers don't sell features that won't be delivered years later - so they can avoid this situation, and usually use feature obsolescence to help drive future vehicle sales.
The curve ball Tesla is throwing at MCU1/FSD owners is that because Tesla has decided not to spend software resources on implementing all of the FSD functionality on the obsolete MCU1 processor, Tesla is now asking those owners to spend $2500 to get closer to the same configuration as current vehicles - if the owner is willing to accept losing radio.
If we don't buy the infotainment upgrade (because it lacks radio), I'm expecting that in the short term we won't get the improved visualizations - and as Tesla continues to add FSD functionality, we'll see a growing list of features not supported on our vehicle.
And since we're likely going to trade-in our 2017 S in 2022 (for a Cybertruck), there will be less and less motivation to spend any money to upgrade the vehicle...