Make smart search indexer working for JSON data of Custom fields

[SemaphoreOxalis]

Hi,
I had a discusion with Tassos Marinos about his ACF Upload Custom fields : I was disapointed when I discover this field was not indexed by the smart search (with right option enabled of course) breaking a lot of dream about site building.
He explain to me that Joomla! Smart Indexr can't use JSON data as used for it field storing path/title/description etc.

Can an "expert" confirm this, and if it's true, there is a possibility this can be possible one day ? Mayb the adoption of Mysql 8 and native JSON field will help ?

Thanks for this community work