I am very looking forward to times where PHP8 is installed on every system.
Many of our plugin users are still on WP<5.9 with PHP7.4. Removing about 14 occurrences of strpos() in favour of PHP8's new string functions has kicked out many of our clients from using our plugin.
Please wait for more significant code changes before deciding to abandon WP<5.9 and PHP<8.0.
Could you please revert this commit and re-commit it next year? https://github.com/wpmetabox/meta-box/commit/8b6f7eae05a1601baa380e1724fe3abcbf2a9595