@Sheilago I'm currently using Drops Air which is 65% alpaca and it is incredibly soft ( I can't have anything remotely itchy near my skin)
However, the reason I'm posting now is because I had a very interesting conversation this morning with a farmer who has 50 alpacas. He got a small number to do alpaca trekking when Covid restrictions started to ease and it's currently so popular he has 50 and is always fully booked.
I asked him if he has a market for his fleeces because I know 2 people who just have a couple as pets and they can't even give the fleeces away to spinners. He said that he has the same problem although he does have one spinner / weaver who will take his fleeces and make items for his ( the farmer's) shop. It is hugely expensive to have them processed.
He explained that alpaca doesn't have the 'hooks' on the fibres like sheep wool so can't be spun in the same way. Also, the fibres in alpaca are abrasive and when mixed with wool will degrade the wool fibres so spinners don't like it. That could be why you found it scratchy.
I see that Drops Alpaca is 100% alpaca so the yarn must be produced by a different method. I notice, looking at a strand of my 65% alpaca Drops Air, that it looks a bit like a knitted tube - it is described on the label as a Blow Yarn. It also says that it is made with baby alpaca which may be softer.
Every day is a school day isn't it!