Respawn Entertainment recently held a Reddit AMA featuring plenty of questions about Apex Legends' design and future content and its process of balancing Legends. Respawn has spoken on Arena weapon prices, Wattson buffs, or even Caustic changes. Live Balance Designer John Larson responded to a fellow developer's tweet following up on some misguided misconceptions about Legend balancing.
While the tweet thread is rather long, Larson makes some rather interesting points.
"High-level assessment of something that GENERALLY holds true in this game: balance changes to abilities don't come close to moving the needle in the same way hitboxes and damage multipliers do in terms of win rate and encounter win rate across all skill levels."
While many players complain about nerfing or buffing a Legends' ability, to Respawn this does little to nothing to make the character more viable. "Changes to abilities move the needle more on pick rate (relatively speaking), and changes to abilities are more meaningful higher up the MMR ladder. Different types of abilities can change this more drastically."
Now this practice does differ slightly when it comes to certain Legends abilities like Caustic's gas which is an integral part of his kit. Increasing the damage to his gas would affect his win rate much more than tweaking Bloodhound's tracker ability.
All in all, Respawn will continue to look at Wattson's kit because of player's complaints even though she has a fairly high win rate.