status error for MSSQL Server Custom Functions

From the README:

Drupal core allows module developers to use regular expressions within SQL statements. The base installation does not use this feature, so it is not required for Drupal to install. However, if any contrib modules use regular expressions, a CLR will need to be installed that is equivalent to CREATE FUNCTION {schema}.REGEXP(@pattern NVARCHAR(100), @matchString NVARCHAR(100)) RETURNS bit EXTERNAL NAME {name_of_function}

I have found the same issue on Drupal 10.2.2. The site is hosted on Windows IIS Server.
Is this a critical issue?

No, it's only a problem if you're using contrib modules that use REGEXP in their SQL queries. This status error is going to be downgraded to a warning - see 🐛 MSSQL Server Custom Functions Error on Status Report page should be a warning Active .