>>11846092
They might be. Chances are they're using some standard phone speakers, like with MM+ -- you can buy Redmi speakers for that one for arguably better bass.
Your best bet would be finding a disassembly video/doing it yourself, measuring the speaker and going through replacement phone speakers on Ali trying to find something that would fit and hope it will sound better.
Or just use cheap but good Chinese IEMs, like Tanchjim Bunny or something.
Picrel was $2, they sound very mediocre, but still better than speakers.