Any issues with enabling "Small Data Mode"?

I run a big multi language site for many years. Are there any issues that could happen if i today enable “Small Data Mode”? Wondering why it isn’t enabled by default.

Yes, it’s an experimental feature. In the future, possibly in 2.10, this might get enabled by default after we work out some kinks.

The reason it isn’t is that for any module that has a default set, if you enable small data mode and erase a field where a default it set, it will still render the default. This mostly causes a problem when you erase a text field as you don’t want that to show but when a default is set, it doesn’t render as empty.