I'm going against the grain here, but although Eraser is ok for removing some things...if you really want a surgical surface prior to LSP, and especially coatings...the Eraser product sits on the shelf. I only use pre-coating prep products like DP prep polish, DG squeaky clean, or the pinnacle or blackfire pre coating products. Eraser does leave a residue. IPA can dull paint and its working backwards in my opinion.
I agree with you entirely about the residue - it is something you can see but also something which you would expect from a technical perspective (looking at the ingredients).
I would perhaps disagree with you about the alternatives noted being better, I would suggest that they are different, rather than better. If I am not mistaken, most of these are 'polish' type products. Such products inevitably contain non-volatile ingredients - it is not just a case of mixing oil and water - they need something to hold the formulation together. In practice, they are going to have emulsifiers which is not a million miles from what is in Eraser and which will be central to the residues it can leave. In other words, the polish type products will invariable leave a little bit of something behind, you are relying that you buff it to death to get rid. If I was wanting to give a really thorough technical answer, the process would have the polish type products you noted but I would follow it with a panel wipe which is 100% volatile (these days I feel that IPA is a bad solution, in isolation).