This person seems insane. You don’t need to pay a “sleep consultant” to make a plan for your child’s nap times. It’s really not that complicated.
If you want to optimise and have the money to spare, I think it's fine. There are going to be people in the world that are better than you at most given tasks, and if working on those tasks is not fun for you and delegation is not a net negative, why not? It's why personal trainers exist (though I don't like them for separate reasons)
In Precious Little Sleep the writer says some half of babies sleep well and some half require help. We must have had the former and so there’s no advice to give. If you were in that set it’s possible that your actions changed something or it’s possible it’s just what it is.
I suppose there are babies with some kind of pathology in this area although I'm not convinced that is what this is.
it's sleep training
it is insane and unnatural but it is also common
fundamentally capitalist concept
contact napping to beyond 1yo is deeply natural and special
For some it is and some it isn’t. My eldest was always a terrible sleeper.
Have you raised kids? This is the least shocking expenditure I've heard of; if this had existed when my kids were born I might have shelled out for it.