Chosen Solution
Suddenly (or so it seems) the steam coming out of the wand is so weak the milk never gets hot. Although I thought steam by definition was always the same temperature, I can put my finger in it with no scalding. Would descaling help or is there a bigger problem?
If the tip of the steam wand isn’t plugged descaling is definitely where you should start; make sure whatever product you’re using actually says “descaler” or “decalcifier” on it. There are a lot of espresso/coffee machine “cleaners” on the market that will not work for this.