If you know anything about how waste should be reduced you’d know the first rule is not to make it in the first place.
But it is not so simple as ‘Nespresso is bad’, because there are environmental downsides to other choices, and it does not automatically follow that because Nespresso uses an aluminium pod for every drink that it is the worst from an environmental perspective.
For infrequent consumption, I suspect Nespresso might have less environmental cost than some other options (especially if a bag of coffee is only partly consumed and then thrown away when/before it gets stale).
Do those posters who condemn Nespresso ever get drinks in takeaway cups? My understanding is that only a tiny percentage are recycled, because only one recycling facility in the UK can recycle the plastic coated paper from which the cups are made, and it is clearly wasteful of resources to make a single use throwaway cup.
Furthermore, how long will those Aldi machines last, given their environmental footprint? I suspect that something made to such a low price point will have a poor environmental performance if it proves to have a lifespan of just the 3 year warranty (or less). Moreover, how many people will decide that they don’t like the coffee it makes or struggle to get it to deliver satisfactory results, and throw it away or stick it in a cupboard. Even the bags which coffee beans are sold in are an environmental cost compared with the large buckets which I have seen used to supply beans to some coffee shops.
I guess in an ideal world we would all have local coffee shops nearby serving good coffee at a reasonable price in good old fashioned ceramic cups.