The naming convention is unfortunate -and I'm more than open to changing it-. I'm not against the opening of the floodgates to any combo being possible, but the loss of defaults just takes away a lot of it .
Allow me to clarify a point that might actually gel with your saying "The naming convention is unfortunate -and I'm more than open to changing it."
Renaming from "Half" is the big thing that needs changed in the books going forward. I would have no problem with a Mixed Elf/Human being an example of a mixed heritage. Heck, the Origins document says "For example, folk who have a human parent and an orc or an elf parent are particularly common. Many other combinations are possible."
It sounds like we can agree on that at least.
I've made my feelings about this more clear somewhere else on these boards, but in short.
It is erasure, you no longer have the fictional construct of people who are different admixtures of humans and elves but who share a culture and form an ethnicity on their own. Instead of them forming a group, now they no longer are a default game construct that demands an answer form each campaign and game. Now we have an atomized bunch of combos with nothing in common, and -worse- which are pure fluff without any mechanical backing. So instead of them being a distinct people, all mixed characters are reduced to one-offs disconnected from the grater world. And by lacking mechanics attached to them, I'm at the mercy of the DM and others just disregarding my choices, because fluff without backing is very easily ignored.
Where we differ is whether or not there should be a unique rules object that provides the same stats for all mixed elf/human peoples. I do want to bring up a point about the narrative. A cohesive half-elf culture does not exist for the published multiverse as a whole outside of specific campaign settings (like the Khoravar of Eberron, or my own, or yours if you have them), and a non-existent multiversal culture isn't being erased. Campaign-specific cultures still exist for these home games. The following text from the 2014 book shows this:
"Half-elves have no lands of their own, though they are welcome in human cities and somewhat less welcome in elven forests. In large cities in regions where elves and humans interact often, half-elves are sometimes numerous enough to form small communities of their own. They enjoy the company of other half-elves, the only people who truly understand what it is to live between these two worlds.
In most parts of the world, though, half-elves are uncommon enough that one might live for years without meeting another."
I would argue that the above quote works as a baseline for any population of mixed heritage peoples.
If a true half-elf culture exists in one's campaign and it is very important that they are a race represented by a specific rules object, fans of the legacy "half-races" will still have those same options to choose because the 2014 books aren't going anywhere, and they will continue to be Legacy options in DDB. Khoravar can still use the 2014 PH entry or the Dragonmarked or other options that exist. The individuals aren't being erased. It also would take very little space in a conversion document to say that "races" from earlier sourcebooks can be played with "X" changes. In comparison, just because there will be new Dragonborn, it doesn't mean that the 2014 dragonborn or the Fizban's dragonborn are invalid. They are still options.
From my perspective, if there can't be a unique rules object for all species-pairings in the new book, none of them should have it. And any rule they come up with has to work for all races outside of the PH. And even if Wizards breaks every PH species into cherry-pickable species-ability options, what about all the species that were not printed in the PH?
I have a question. If in 2025 you invited someone to in your home game, and they wanted to play a "half-elf" but they had the stats of an elf or a human, would you allow that?
