I need to pick up another MBP for programming work and Big Sur just obsoleted the 2012 MBP which has me second guessing picking up a 2015 model because it's the last year of that generation and I fear that Apple will obsolete that generation relatively soon. There are a number of reasons why I prefer the previous gen to the current gen, not the least of which is not having to pay Apple $724 to replace the SSD if it goes bad. Therefore, how much more life do you think the 2015 MBP has for future OS support?