What are ARPU benchmarks for mobile gaming genres?

This is an antiquated way of looking at monetization -- I don't know of any serious companies that think about user metrics broadly in terms of global ARPU or LTV. The companies that do user acquisition well at scale tend to focus on Day 30 - 60 - 90 ROAS.

The most successful strategy games should regularly produce blended ARPDAU metrics over $1 (much higher during events and sales) and often look to fully recoup spend in under 180-240 days. Casual games might look for recoup at the lower end of that timeline scale. Hypercasual games tend to want to recoup their UA spend inside of a week.