"They" are irrelevant for SeedSigner since you can build it yourself and run the FOSS code completely permissionlessly. Those of us involved in the project have NO IDEA who has built a SeedSigner.

I disagree with your definition of "product". I think of a product as something that a company sells. We're a completely open source PROJECT. If you build a SeedSigner and run our code, none of the volunteers who work on the project profit from it.

SeedSigner + Silent Payments is a FOSS project adding (currently experimental) support for an open source protocol / technique.

No one asked me to start building support for Silent Payments in SeedSigner. No one paid me to do it.

I've spent quite a bit of time with bip47 in the past. Interest in bip352 is a natural progression.

Some conspiracy theories are interesting or incisive. This one isn't.