"Bose blows" is typically in regards to their price/performance, and especially with how they marketed themselves throughout the 90s and early 2000s.

Bose used to advertise that they were the best sounding speaker out there, while also running advertisements that made claims which violated the laws of physics.

For the same price as a Bose system you could get something much higher quality. Bose was selling at luxury prices w/o luxury quality. They got away with it because compared to the cheap garbage most people listened to, Bose's stuff was nicer. Their quality was mid to upper mid tier, and the build quality was generally good.

But people got irritated by a decade ads saying a tiny speaker is more powerful than a proper speaker setup.

Now days Bose makes good quality noise cancelling headphones (and I suspect they made more revenue selling NC headphones during the open office and then COVID era than they ever did selling speakers in the 90s!) and they brand car stereo systems.

Their noise cancelling headphones are good, even if the ear pads wear our way too fast.

Pretty much no one has a home hi-fi setup anymore, everyone just has a sound bar. I do have a hi-fi music setup, people are rather shocked when they come over that I even bothered. I got it for $2k on Craigslist years ago, the setup cost someone a small fortune when they were brand new. IMHO buying new hi-fi gear is pointless, Speakers made in 2005 sound just as good as speakers made in 2025, the laws of physics haven't changed any!

Speakers often use materials that degrade over time unfortunately. For example electronics in the crossover, foam, glue, and depending on the environment paper.