For what it’s worth, Nichia’s datasheet, which Clemence links from his store, does chart the shift in chromaticity coordinate with varying current.
The way I see it, bare LEDs are not consumer products. As with other products intended for industrial use, they’re intended for expert users, and sellers might reasonably assume buyers are willing to take a risk buying a few units to see if it will work for their application. I say this having destroyed every E21A I’ve ever owned - most of them through user error.
I do think E21As behind a diffusion screen are likely a good fit for OP’s application.