I doubt the (relatively) budget G-Sync panels will be going anywhere. At the end of the day, look at the numbers quoted of FreeSync panels that are actually verified/certified as fully G-Sync compatible. It's <10 vs 3000 tested panels (or something like that).
While it's going to be possible to enable G-Sync, it's not going to be as great an experience as a 'true' G-Sync panel. Even the select few certified models are likely to differ.
If anything, there might be a slight pricing reduction overall (as in, for the modules/licensing) to ensure 'true' G-Sync remains an attractive proposition.... but G-Sync has always carried a premium - so I wouldn't anticipate a whole lot changing.