Another rationale from "Inclusive Chromium code":

Terms such as “blacklist” and “whitelist” reinforce the notion that black==bad and white==good. That Word Black, by Langston Hughes illustrates this problem in a lighthearted, if somewhat pointed way. These terms can usually be replaced by “blocklist” and “allowlist” without changing their meanings, but particular instances may need other replacements.

https://chromium.googlesource.com/chromium/src/+/master/styleguide/inclusive_code.md