McIntosh was spun off twice already by Private Equity. It wasn’t sustainable for Mac to continue to be bought and owned by Private Equity. A PE firm buys companies as investments, they know many won’t survive and only a percentage will hit, allowing them to flip those investments for a profit. Generally, what they do along the way is build up market share and revenue but not necessarily profit, for many companies this leads to bankruptcy or various pieces being sold off leaving usually the weakest pieces of the business left with an unsustainable, survivable amount of debt.
Bose appears to be buying Mac as an entrant into the HiFi, Audiophile club. They likely paid a lot of money for the company, name, branding and market position. They could really mess everything up with poor management or if they decide to reduce cost, cheap out on the quality of parts, design, engineering but their main goal going in is to maintain the Iconic Brand and position of Mac along with enabling true, profitable, sustainable growth. That’s a vastly better starting point than a PE firm. It could all go to you know what but if Mac continued to be churned through the PE machine being bought / sold every 7-8 years it was inevitable Mac would have eventually faded away either quietly over time or potentially in an epic fashion.