Someone doesn't understand how cellphones charge. Any 5 Volt charger is "compatible" with any current cellphone. So is any 15 Watt charger, any 25 Watt charger, any 45 Watt charger, any 65 Watt charger - and anything they come out with in the future that can charge at higher power. It's the "can" that's important. A 65 Watt charger isn't going to force 65 Watts into the phone, the phone draws whatever it draws from the charger. The phone determines the charging rate (as long as the charger can supply what the phone is trying to draw).
Your house, if you live in the US, is a power supply that can handle approximately 44,000 Watts. That doesn't mean that a 100 Watt light bulb will burn out - it draws only 100 Watts. (My shop charger, back in the day, was a 5 Volt, 30 Amp supply. We used it to charge all the phones that came into the shop (and we could easily charge a dozen at once). No phone ever drew 30 Amps, each one drew what it drew, whether the "charger" was rated at just that, or at 30 Amps.
An S21 is "compatible with" an old Samsung 2 Amp charger (10 Watts) or a 65 Watt charger. It will charge with no problem with either one. (It will charge faster, from any given point, with the 65 Watt charger, that's the only difference.)
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