The account did not break Twitter's rules.
- The tweet did not link to Mastodon.
- The tweet did not name a Mastodon handle.
- The tweet is not similar to any of the examples provided in the deleted policy (“follow me @username on Instagram”, “username@mastodon.social”, “check out my profile on Facebook - facebook.com/username”).
- The tweet did not bypass restrictions on external links via means such as URL cloaking or plaintext obfuscation, with the example provided being “instagram dot com/username”.
- The CEO of Twitter stated that "casually sharing external links" to competing platforms is "fine" when the deleted policy was in place: https://twitter.com/elonmusk/status/1604593057676300288
Even though the account did not break Twitter's rules, you believe that it should have broken Twitter's rules because the tweet said something that hurts Twitter's business prospects. This is what you are erroneously using the phrase "ban evasion" to describe, even though Twitter's policy on ban evasion (https://help.twitter.com/en/rules-and-policies/ban-evasion) defines it as something done only by accounts that were previously banned or suspended.
HN does have it right this time. HN users are fully capable of seeing that the novel definition of "ban evasion" you invented specifically for your argument does not match the definition used in https://help.twitter.com/en/rules-and-policies/ban-evasion.