Before You File a Bug Report Please Confirm You Have Done The Following...

• I have tried restarting my IDE and the issue persists.
• I have updated to the latest version of the packages.
• I havesearched for related issues and found none that matched my issue.
• I haveread the FAQ and my problem is not listed.

Playground Link

https://typescript-eslint.io/play/#ts=4.9.4&sourceType=module&code=DYUwLgBAbghgTgSxgI1BAvBARCgxliGAZwiLEQDsBzCAH2gHsEATAbgFgAoL2RFUAPwA6ANoAGALqsgA&eslintrc=N4KABGBEBOCuA2BTAzpAXGUEKQAIBcBPABxQGNoBLY-AWhXkoDt8B6Jge1tiacTJTIAhtEK0yHJgBNK+SpPRRE0aB2iRwYAL4gtQA&tsconfig=N4KABGBEDGD2C2AHAlgGwKYCcDyiAuysAdgM6QBcYoEEkJemy0eFYDAruuGAL4g9A

Repro Code

letvariable="abc"asstring|void;variable?.[0];

ESLint Config

module.exports={parser:"@typescript-eslint/parser",rules:{"@typescript-eslint/no-unnecessary-condition":"error"},};

tsconfig

{"compilerOptions": {"strict":true  }}

Expected Result

No problems

Actual Result

The third line reports an error -Unnecessary optional chain on a non-nullish value.

Additional Info

Related to#5766. That PR did not extend to the optional chaining part of this rule.
This is caused by