Here's a thought to consider....

Want to protect your assets?

For the first six months that new products are released, lock them down hard. Issue a dongle that proves identity. Or a secure keychain that requires a log on. Or an secure key app that provides a cycling code. Or make users renew their decrypt key every two or three days. Or keep some of the model code on a server and make the user refresh that code every two or three days.

No minimal security. Lock it down just as tight as possible.

Then, after six months, unlock it and leave it decrypted.

Forget the old products that have already been released. They are already out there. Those cows are out of the barn. Trying to corral them back in is a waste of resources.

People don't want to buy DRM content? Wait six months. People are worried that Godzilla will nuke Salt Lake City? You only loose access to items bought in the last six months instead of forever.

Just don't try to sell me a 1976 Nova and claim that it is as safe and reliable as a 2015 Toyota.