Not legally in many places. California limits exhaust levels to 95 dbA or less, and I'm betting that OP's mods violate that given that "ATAK exhaust systems produce the highest dB (decibel) levels in the Borla line" [0]. Washington state prohibits modifying exhaust "in a manner which will amplify or increase the noise emitted by the engine of such vehicle above that emitted by the muffler originally installed on the vehicle" [1]
> Have you considered that maybe this guy just likes the car?
I'm inclined to give the same amount of consideration for this guy's preferences as he is towards the thousands of people he chooses to subject to unnecessary, annoying, unhealthy[1], and likely illegal noise.
[0] https://www.borla.com/products/atak
[1] https://app.leg.wa.gov/rcw/default.aspx?cite=46.37.390
[2] https://noiseawareness.org/noise-hurts/impact-on-health/