It`s not common to spend two hours per day on WaniKani. I sometimes do it if I level up and do all 100+ new lessons on the same day, but I haven’t been doing that. Once you’re past level 5 or so, you will spend maybe 30 minutes/day on reviews, but you can do them little by little on pockets of free time throughout the day, you don’t have to allot haf an hour of your leisure time for reviews. You can do them on your phone. Lessons will take you a little longer, and it is better to sit down and do them carefully, but even if you go at the fastest possible pace you will only unlock new lessons every 3 or 4 days.
Your accuracy also greatly affects your workload - if you keep getting items wrong, they’ll keep showing up for reviews more often. Pay attention to your lessons and get them right, it pays off. Also search the forums for the override script, it will avoid being held back because of typos - but don’t abuse it.
WaniKani requires a significant time investment, but it pays off. Search the forums for the resources thread, there’s plenty to do while you’re waiting for reviews during the first few levels.