ArsTechnica has an excellent article that goes over the average number years of support Macs get, broken down by OS feature updates and OS Security updates. It doesn't bode well for pre-transition computers processors.
Dropping old Macs can be justified, but some are dying before they should be.
arstechnica.com
Not to mention if you're running Windows 10 in Boot Camp on your Intel Mac, support for that ends in October 2025. Windows 11 can only be officially virtualized on Intel Macs since the TPM chip they have isn't compatible.
Assuming we get a Apple Silicon Mac Pro early next year, that will be the last computer to transition. This process started in November 2020, so I'd expect it to be done within 5 years:
- 2022 - macOS 13 - Drops support for any 6th-Gen or earlier Intel Chips
- 2023 - macOS 14 - Drops support for any Mac without T2 chip
- 2017 MacBook Pro, 2017/2019 iMac, 2017 Macbook
- 2024 - macOS 15 - Drops support for any 8th-Gen or earlier Intel Chips
- 2018 MacBook Pro, 2018 Mac Mini, 2018/2019 MacBook Air, 2017 iMac Pro
- 2025 - macOS 16 - Drops support for all Intel Processors
- 2019/2020 MacBook Pro, 2019 Mac Pro, 2020 MacBook Air, 2020 iMac
TL;DR: Expect your 2020 MacBook Pro to stop receiving feature updates in 2025 and security updates in 2026.