[kidfiji]

On a much smaller scale, this is the same reason why distilled water is widely not recommended for use for espresso machines. Its lack of minerals will attract metal ons from internal parts of the espresso machine, which can cause corrosion.

[karmakaze]

Distilled water is also said to taste bad on its own from the lack of minerals.

One reason given for why Starbuck's Americanos taste good is because of their water filtration[0] (as long as you 'leave room' and don't add anything else).

[0] https://www.tastingtable.com/928069/why-starbucks-water-tast...