I'm pointing you toward how things are meant to work, not arguing with you or leading you through your research.
If you want to skip paying $150 for a Pixel to use on Graphene or Calyx or something halfway decent, and "just use Lineage how bad could it be", be my guest!
The "Support length" table at https://calyxos.org/docs/guide/device-support/ shows that CalyxOS supports a bunch of devices even after the vendor drops support. For example, support for the Pixel 4a 5G ends in October 2023, but CalyxOS plans to support it until August 2024. It's unfair to recommend against LineageOS for doing that while supporting other custom ROMs that also do it.
Also, for supported Pixels $150 or less, https://swappa.com only has the Pixel 3a, which loses manufacturer support next month, and the Pixel 4, which loses manufacturer support 6 months from now.
If you want to skip paying $150 for a Pixel to use on Graphene or Calyx or something halfway decent, and "just use Lineage how bad could it be", be my guest!