And yea, I agree with the article. In my past I've also dabbled in audioreactive for LEDs and it's fiendishly difficult to make anything interesting.
Make it react too much, and it's chaos, and inversely when the algorithm reacts less the audio, it's boring.
And in all cases it's really not easy to see what the leds are doing in correspondence to all the complexity of music.
For my use case I want something fully portable and battery powered anyways. So the audio stuff should happen on the ESP32. (Or on my phone, that might work too)
Everything is relative, though. In terms of maximums, a Pi 4 (for example) can use up to about 7 Watts under load by itself, which adds up fast when operating on batteries.
But a single 1 meter string of 144 WS2812B LEDs can suck down up to around 43 Watts, and 43 is a lot more than 7. :)
Lighting rigs are thirsty. The processing (even if it's the whole Pi) is generally a small drop in the bucket.