Usually I'd be on your side, but the fact of the matter is that they weren;t using the word correctly. To fit the definition it needs to either be a worn item or to contain a physical relic, and the lich's "phylactery" generally checks neither box.
Now I just wish they would stop using the word "race" incorrectly. Tgat's the big onenthat's causing problems, and the only criticism I can legitimately give this decision is to raise the possibility that they may have deferred that important change to deal with this minor one.
Heh, I think that come the new release of 5e, the term "race" may have
ahem run its course.
I can just imagine the midden hitting the windmill when WotC makes
that announcement though.
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As far as the moral angle goes, well, frankly, that's unavoidable. There is a moral dimension here. Using cultural concepts incorrectly is wrong. It's all wrapped up in cultural imperialism and various other issues and, since there is a moral aspect to this,
@Galandris is correct in saying that any change is going to receive push back. I'm not sure that there's really anything that can be done to avoid that. For example, if they do remove the term "race" from the books, that's really tantamount to making a moral judgement on the past, no matter how you spin it.
Honestly, the only way forward is through open engagement and a willingness to listen and respect other viewpoints. (and, yes, I am perfectly aware of the irony of me saying that, thankyouverymuch) It's just something that is going to take time, just like any other social change. I grew up using language that would not be anywhere near acceptable to use now to refer to all sorts of different people. As did everyone around me. Autistic might be the word now but it certainly wasn't in common usage when I grew up. But, times change and we need to adjust.