Again, following you logic, Elecraft could never have gotten off the ground. But HR "moved on" to innovation which brought popularity of a new brand and old brand names. Capitalism works!
That isn't what I'm saying. Every company has to reinvent itself every few years now because technology and competitors are constantly changing. Partly because of this constant change, anybody can start a new company from scratch if they have a plan to make something that people are going to want, and they're able to raise the capital to invest in development and manufacturing before the sales start rolling in. There's a large graveyard of ham providers who didn't change quickly enough and are now gone, but there are plenty of others who've been innovating and have guessed right about what people will buy and have managed to start from scratch in the past decade (Elecraft, Flex) and are well-managed and are doing well.
The steam went out of TenTec starting about a decade ago, so what Mike bought was a product line that was already pretty long in the tooth. There are plenty of TenTec fans who'd probably buy one of the old designs if it was offered today. Mike wouldn't have to sell as many units as Icom's IC-7300, but he'll need
something to sell.
I just took a fresh look at the tentec.com web site - you can't buy anything, even parts, so it really looks as if TenTec is dormant. Maybe Mike has a great team together working hard on an amazing new SDR radio that we won't be able to resist, or he'll start producing and selling an older TenTec analog rig that people might want because they like the way TenTec rigs of yore work. In the meantime, at least viewed from the web, TenTec isn't open for business at this point if you're looking to buy radios or parts.