I think the problem is not in pod-based single-serving coffee machines. Those are common, and well-loved for a reason.

But there are easily available alternatives that do the exact same thing without requiring so much plastic, namely Senseo coffee pads (they’re grounds in coffee filter paper) or CoffeeB and its compressed coffee grounds balls (so it’s all just coffee ground, both the coffee and the pod). Probably a fair few more I don’t know about personally.

Possibly even Nestle with their Nescafe pods. They’re aluminium but some countries achieve effectively 100% recycling on that, then the only issue is the filter membrane they place inside and I don’t know whether that is easily separated during recycling or not.