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• I havesearched for related issues and found none that match my proposal.
• I have searched thecurrent rule list and found no rules that match my proposal.
• I haveread the FAQ and my problem is not listed.

My proposal is suitable for this project

• I believe my proposal would be useful to the broader TypeScript community (meaning it is not a niche proposal).

Link to the rule's documentation

https://typescript-eslint.io/rules/prefer-nullish-coalescing

Description

Following up from#5748 (comment):

We should give [prefer-nullish-coalescing] the same treatment as rules like strict-boolean-expressions where the rule will explicitly error if you don't have the option turned on.

https://typescript-eslint.io/rules/strict-boolean-expressions/#allowruletorunwithoutstrictnullchecksiknowwhatiamdoing

I would say we can do that change without a breaking change because the rule is LITERALLY useless without the option.

Fail

n/a

Pass

n/a

Additional Info

#5988 added docs; now let's add a runtime check. 🚀