Manley Laboratories sells principally to the Pro audio business. Consumer gear was a sideline and high-end consumer audio is declining as well. I'm guessing that there has been a considerable decline in Pro tube audio gear over the last 10-15 years. You can make good products but you need to have paying customers in order to support a business.
EveAnna has sold her biz
Ralph Karsten has been vocal as to the uncertain future of tube gear. This is a punch to the gut. My totally unsupported hunch is that EveAnna has the same concerns. I always wanted to have one of Manley's 300B amps. I don't know now. I am a very happy owner of a Steelhead phono stage for ten years. Eventually the outboard power supply will fail (they always do) and I may be without the ability to have it serviced if this new owner ends up closing shop.