Wrong detect of Parsing error: invalid-first-character-of-tag-name in expression.
Thank you for the report.
This is a correct error as according to HTML spec:invalid-first-character-of-tag-name error.
Tag open state’s Anything else step.

To make valid HTML, you should use < instead of the <.
Or you can ignore the error by the option of vue/no-parsing-error rule: https://github.com/vuejs/eslint-plugin-vue/blob/master/docs/rules/no-parsing-error.md#wrench-options

Use &lt for <, using the xml escape
https://owasp.org/www-community/password-special-characters
" !"#$%&'()*+,-./:;<=>?@[\]^_`{|}~"
After escaping, it looks like the followinghttps://coderstoolbox.net/string/#!encoding=xml&action=encode&charset=us_ascii
&quot; !&quot;#$%&amp;&#39;()*+,-./:;&lt;=&gt;?@[\]^_`{|}~&quot;