Maybe I am naive, but in that case, what about someone teaching the parents how to do the work?
I agree that the SALT my DD1 had was a waste of resources. Not because her problems are non-existent. She has severe delay in both expressive speech and receptive language, severe delay in speech clarity, and word-finding problems, and so on.
However, her SALT sessions, which only materialised because I complained about the quality of the SALT, were completely ineffective. An hour at a time of trying to keep DD1 at a table, doing 'book' work, when the room was filled with interesting things that would have engaged DD1. It was only at the last session that I finally said 'what about if you do one thing you want to do, then let DD1 choose one thing', because the SALT was getting nowhere fast.
I would have gladly listened and learned what to do if someone had offered that. I have been asking for 2 years.
The thing is that language and speech development in NT children is just effortless. I say 'frog' to my 16 month old, there is a pause, and she says 'frog'. She is picking up several words every day. She is picking up Makaton beautifully too. She signs and says 'please', 'thank you', 'sorry', 'all gone', 'juice', 'hungry', 'more', 'yes'. She says two word familiar phrases 'do again', 'get down', 'help please' and lots of single words.
But language acquisition and speech development just isn't like that for DD1. She relies on learned phrases. She sounds like a (slightly bizarre) mini-adult. I haven't had any guidance about what will work with her, and everyone I see has a different opinion (use PECS, no use Makaton, no just keep modeling good language, etc.)
I can see it must be frustrating from a SALT's perspective, but for many parents, the experience is that we are left floundering, knowing that the SALT is a waste of time, but not having an alternative.