> Regarding the different collation algorithms: The unicode variants should be slower than the general variant due to the more complex algorithms, but this was years ago when computers were much weaker than now. With modern hardware, the speed gain should be hardly notable.

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> Furthermore, we should prefer accuracy over speed. There is no need to use an old and quirky collation like utf8mb4_general_ci with modern hardware.

This is kind of oversimplified and depends a lot on your use case. Performance can absolutely matter even with modern hardware. There is no one-size-fits-all collation that is best in all scenarios, if there was, we really wouldn't need the option to choose.

If you have a thousand rows in your table, sure, use whatever. If you have a billion rows in your table, things are different and you may not be able to afford leaving performance on the table.