Thunderbolt is an Intel-exclusive thing. You can't get the spec without signing various legal agreements with Intel. Every Thunderbolt device needs to be approved by Intel. USB4 provides the same functionality with an open spec, free for anyone to download. We need more open specs.
It used to be an Intel-only thing. Not anymore.
In so far as approved, I hope you mean simply certified by some certification house like any other transmission standard (like displayPort or HDMI and such countless others). Royalties have ended if I recall back in mid 2019, and USB-IF (Universal Serial Bus Implementers Forum) have taken the reigns, and is what USB4 is being built on. This also means manufacturers can also produce TB3 silicon if they wish (where before those rights remained with Intel, AND you had to pay a single royalty fee).
Am I getting this right? You are OK with a device having a single USB-C port providing either USB3 OR Thunderbolt connectivity. You are OK with a device having two identical connectors, one for USB and one for Thunderbolt. You are not OK with a device having a single connector providing both protocols. I don't understand.
If you need your questions answered directly, just read the bolded portion for a quick TL;DR
I'll be as clear as I can. This whole issue started with false specification/standard advertising. Saying something is HDMI 2.1 certified, but then when you look, you see if fails specification. The specification creators have started over the past few years including "optional" portions of standards which is a contradiction in terms, and is a disastrous (in my book fraud) to allow devices to advertise passing a standard, when no apparent differences exist until you test or dig deeper into manuals as to the actual portions of a standard they've implemented.
That is the big issue here for me. You brought up physical connectors and their similarities but differing capability, to which I really have no qualms with generally speaking but ONLY IF you are being sold precisely what is being advertised to you. I don't want Thunderbolt 3 advertising on a product that would only function as a general USB Type C transmission cable certified only for something like USB 3.1 Gen 2 transmission rate, or features.
The only issue I have with that ordeal, is the naming schemes are simply confusing people (USB-IF are actual morons in this respect, they've made a complete mess since USB 3.0 and later). But as long as you get what is advertised. That's fine.
Again, my issue was with fraudulent atmosphere surrounding specifications and standards lately. And the advertising allowances. The biggest problem being again - as I've said - when a company advertises for example HDMI 2.1, there is no way for me to know how many portions of the standard they're actually implementing. This is running rampant especially within HDR standards, and things like Variable Refresh Rates of panels.
So to your question:
You are OK with a device having a single USB-C port providing either USB3 OR Thunderbolt connectivity.
Not unless one standard includes ALL portions of the other specification in terms of performance. Like if Thunderbolt 3 provides all the prior aspects of USB-C's various iterations (aside obviously from the physical connector shape which it doesn't), then it's fine in my book. Just a bit silly or pointless I suppose.
You are OK with a device having two identical connectors, one for USB and one for Thunderbolt.
Again, that's fine with me, so as long as each function to specification as detailed by each specification. Again, the only qualm with this, is just idiotic confusion for consumers that might get confused if they're not familiar with the confusing naming schemes that are complex for no reason.
You are not OK with a device having a single connector providing both protocols.
No problems there as well. Again, the biggest problem isn't in protocols or connectors themselves. It's the specification forums that are allowing companies to get away with certain advertising claims, that allow a sticker to be put on the device, and both devices don't perform the same due to leniency through optional portions in a specification.
Like if company A makes a TV, and company B makes a TV. And BOTH advertise HDMI 2.1 certified. One could potentially have Dolby Stream Compression capability, while the other doesn't. THIS is at the crux of the issue I have with "standards". Why are they calling them standards when they allow for optional portions? This is defiance of intuitive use of the word "standards". If it's optional, companies could do it themselves on their own, you don't have to tell them "it's optional".. Stop allowing advertising of supported standards, when one company could just do the bare minimum for a supported standard, while another could potentially fulfill the entire specification list. THAT is my main problem here.
The issues you brought up about connectors and confusion born from that ordeal is a seperate issue I don't have much issue with as I said before. As long as no lying is occurring with what you're being sold, then that's fine generally.
