I have measured peaks using very dynamic music and I never got above 20dB difference between average and peaks.
Perhaps if you have some classical music which starts off softly and ends in a big crescendo ... perhaps you could reach those numbers.
Here are some real world measurements with 'level descriptions'
IMO you need to be able to reach 120dB SPL and then you have no worries about clipping even when playing uncomfortable loud.
Those that want to be sure can add 6 dB more headroom (double the required output voltage = 4x required output power)
Ananda reaches 130dB at 1W so even at 0.5W it already complies to the 'rule' above including the 6dB extra headroom.
Most likely when listening to music for enjoyment and relaxation you will not even reach 1mW.. unless you have some really inefficient headphones
Ananda can reach 119dB with 1V (phone output).
The AudezeLCD2 is a LOT less efficient. It needs 11V to reach 126dB = 1.8W instead of the 0.5W of the Ananda.
The fact that some drivers can handle 4W does not mean you will ever use that unless you have them lying on the table and use them as little speakers.