Capped max phone battery & battery protection

Since due to US and EU laws phone makers manually cap the max capacity of phone batteries vs the ones they sell in Asia or India, does it make sense to use battery protection (that makes it so your phone charges to 80% ) ?

For example the global version of Redmi Turbo 4 is the Poco X7 Pro.
The Redmi is sold in China and has a battery of 7550mAh while the Poco has 6000 mAh.
They have the same battery but it capped for the Poco.

So question is since the Poco battery is capped and will never reach its (real) max charge (of 7550 mAh) anyway, why not charge it at 100% ( 6000 mAh) all the time?