nraymond
500+ Head-Fier
I don't know the details of RHA and Audiofly, but I would not characterize what happened to Onkyo and Aiwa as something caused by COVID. The fall of Onkyo is due to Gibson (the guitar company), which I talked about back in 2017 here:Covid killed a few boutique audio companies - RHA, Audiofly, Onkyo, Aiwa for example. Even Sennheiser as you said, had to sell away their consumer wing.
Sad, but it is kind of a survival of the fittest game going on. The audio hobby is considered "discretionary spending". Consumers will know whether something is providing good price-to-performance or not. CHIFI generally are much cheaper than some of these boutique brands and if a company rests on their laurels, and continue selling overpriced gear without innovating, then they may face the music (literally).
https://www.head-fi.org/threads/gibson-facing-some-challenges.867057/
Aiwa lost their profitability in the late 1990s and was bought out by, and became a sub-brand of, Sony in 2003 (Sony had been a majority stake holder in the Aiwa company for many years). Sony tried to keep Aiwa going as a sub-brand but gave up in 2006. In 2015 the Aiwa brand name was bought by US company Hale Devices for use in selling products with that brand in the US and a few other regions. Hale Devices also renamed themselves to "Aiwa Corporation". In 2017 Towada Audio in Tokyo bought the Aiwa brand rights from Sony. In 2021, Aiwa Corporation in the US filed for Chapter 11 bankruptcy. Towada Audio continues to make and sell Aiwa branded products in other countries.
I'm not sure what connection there could be between Sennheiser selling their consumer business to hearing aid specialist Sonova and COVID.