I recall seeing a news report a little while back, about an engineering company in the UK, which was in exactly that situation. They'd reached the point where, if they didn't start training some new guys up soon, they were going to go under, as everyone hit retirement.
Well then do that. (large) Companies themselves are to blame as well. They've been waiting for the government to bring them free educated and trained labour for decades and then expect them to also have the work ethic and then pay them half ass wages in the process.
This whole "I'm entitled to top class labor cause I pay some taxes" again comes from the boomer generation.
It's best for Gen Y and now especially Z to understand this quickly and start their own business and learn their own skill because an employer these days will just use you to fund their inflated retirements while not giving one ounce of dog poo where you will end up.