We had a pilot join us a few years ago after being away from flying for 10 years. This didn't present any major problems as he was a good operator and after a few months in the right seat he got back into the left again. All the Captains he was flying with were doing 80+ hours a month so their currency wasn't an issue and he would have been easier than most new first officers to fly with. He was also the only pilot in the company at the time who had been away for such an extended period.
The current situation is unprecedented so we don't know exactly what it will be like last year when hopefully there will be a significant improvement in air travel. Airlines will be faced with a situation where most crews are short of recent experience and will have to appraise them before returning them to duty. Some pilots may be able to get back easily with minimal training, others may need much longer to get back up to speed. The present system of restricting "green" crew from flying together might have to be applied to ensure that a Captain and F/O who have both been out of the flight deck for two years aren't rostered together.
At the moment I'm happy with my sim performance and think I could do the same in the aircraft if I had to but don't feel the need to try until I'm a bit more current.