Not legal advice, but I believe denying all facts even the ones that are obviously true is setting himself up to pay costs for proving those facts, even if he was to win overall.
Nintendo are over litigious and have a reputation for weaponising copyright laws to shut down legitimate competition - but I suspect this might not be a good test case for challenging this.
TIOBE is meaningless - it is just search engine result numbers, which for many search engines are likely a wildly inaccurate estimate of how many results match in their index. Many of those matches will not be about the relevant language, and the numbers probably have very little correlation to who uses it (especially for languages that are single letter, include punctuation in the name, or are a common English word).