I'll be honest, the entire OneDnD experience turned me sour on DnD as a whole. It was a chaotic mess from beginning to end, with no clear goal in mind and full of missteps and retraces.
They were writing down things that were clearly not going to end on the final product (Wish as a capstone for two or three different classes, or the Wizard's Modify Spell thing that was balanced around players not having enough money to actually use it) and half-assing things that they didn't give a shit about (Barbarian and Monk especially so, but the Brawler was another example, too).
They kept asking players to judge things without giving them a clear vision of the experience as a whole. Compare OneDnD to DnD Next, where players were given all the classes from the beginning so that they could compare them to each other, monsters stat blocks to playtest them against, and even sample modules so that everyone could have the same playtesting experience.
Now compare that to OneDnD, where the players had to wait the sixth playtest (out of eight) to finally have the chance to see the last class (and it was half-assed as well! The Monk would not see a genuine attempt at improving it before the very last playtest). The players were given nothing to playtest them upon, either, and the classes had no common ground because each playtest had different rules (such as the Bard, which was only playtested with the old spell lists rules that were eventually reverted).
Heck, for the most part we've been asked to playtest spellcasters without having a clear understanding of how spells will behave in OneDnD. Will they be nerfed? Will they be improved? Aside from some cantrips (which we've been told they'll be buffed on the second-to-last playtest) and a pitiful amount of spells (most of which appeared in the last playtest) we have no idea.
And the entire playtest revolved around a boolean yes/no question with no in-between. Get enough negative reception and the thing gets scrapped right away, even if the concept was good and people wanted another iteration of it (like wild shape stat blocks); get enough positive reception and the thing gets written in stone even if people would've loved to see it improved (weapon masteries, for example).
This is an example of how not to do a proper playtest. I'm grateful it's over, because it was a shitshow from beginning to end.