Silent Thread Reborn includes new and revamped missions, it's not analagous to Black Mesa
I'm sorry, but you're being incredibly arrogant. In the aforementioned BBC article:
The Black Mesa team has also edited the storyline to beef up the more engaging parts of the game and eliminate the slower parts.
I'm pretty sure that's exactly what ST:R did with the original Silent Threat's story.
SCP is updating the code and adding new features, same deal.
So
what about these features that weren't present in any Valve-endorsed Source-powered game?
FSU is just a HD upgrade to the original game and benefits many other mods, again, not analagous.
It's pretty well established that Black Mesa is more than just an HD upgrade. If it weren't more than that, it would require Half-Life: Source to run (since, by your logic, it's just an FSU-like upgrade). Which it doesn't.
The mod is freely available. Since the mod team can't exactly "patent" code out of a game mod, anything they've added to Source not previously released--including all features, textures, models, etc.--will become available to the public and probably benefit many more mods to come.
I love how people always get defensive, put words in my mouth and jump to the worst possible conclusion.
FSPort didn't waste their time so long as they enjoyed what they're doing.
But you've insinuated that Black Mesa wasted their time. And don't claim otherwise; you said so right here:
Why spend so long remaking a game when the first game is perfectly playable and readily available? Bizarre.
All that aside, I share your sentiment on the next official Half-Life installment. If it exists, I'll definitely preorder it when the time comes. If not, someone will eventually make a fanmade ending to the chronicles of Gordon Freeman. Having an ending to the Half-Life arc--however long it may take--is not only possible, but it's inevitable, fanmade or official.