The recent options offered by Tesla, like MCU1 to MCU2 upgrades (which have evolved in various flavors of lower cost according to the state of the MCU1 and the screen), CCS upgrade in EU (with price decreasing significantly), the eMMC repair done by Tesla now instead of full MCU1 replacement, also at a much lower price... These are all for older cars. They all extend old cars’ live spans significantly, in terms of usability and convenience.
It would make sense for Tesla to also offer battery upgrades as soon as cars start reaching the end of the 8 years battery warranty.
Which is about end of this year.
It is also in line with the sustainability value they push forward.
All in due time imho.