Overkill in some cases perhaps but with modern amp technology no real downside, all else held constant, at least these days. It’s like an oversized engine in a car. Worst case you are paying for an insurance policy. In years past, extreme size, heat and weight were common downsides.
Too Much Power
Please bear with me as I am nowhere near an expert at this type of thing...
I recently read a review of the PS Audio Stellar M1200 mono amps. I was somewhat taken aback by their power rating of 600 watts at 8 ohms/1200 watts at 4 ohms. Made me wonder what, if any, are the drawbacks to that much power? Welcome your thoughts...