Of couse not but before you give a diagnoses you need to look at other possibilities. if cutting out a drink helps a child cut it out. If setting firm boundaries helps do it.
Do you have kids? If so, if your child literally woke up one day having lost a significant proportion of the skills they’d acquired, what would you do?
Would you try absolutely every single thing you can think of to help them? Or would you just sit back and wait 12 months for a diagnosis and then still not bother to do anything?
Why would you assume parents of children with ASD would do the latter when any reasonable person would do the former?
You honestly cannot imagine the lengths I’ve gone to and time and money I’ve spent trying to help my boys. Most children learn to play through their own exploration - mine didn’t so need constant adult support to even stack one block on top of another. Most children learn to talk just from listening and observing. Mine haven’t, so every interaction is made up of speech therapy techniques and I spend my days laminating and cutting out PECS cards, trying to coax exchanges out of them even when I know they want a drink but I need them to learn to communicate that. Most children learn from watching and copying others but mine don’t so I have to sit and copy them and hope they notice. Most children respond to verbal instruction - good luck taking two nonverbal preschool kids with ASD for a walk to the park on your own.
And that’s not even getting into the hundreds of hours I’ve spent fighting for the right specialist school for them, rather than the cheapest.
All for things other parents take for granted and can just do.
And no matter how much I do for them, there will always be people who think my children just have shitty parents.