...let's be honest, this applies to *every* game with Online PvP in it and is not limited to Ranked Crystalline Conflict or The Feast. The average player going for the common coping mechanism of rejecting blame is also fairly common elsewhere, but specifically in FFXIV chat gets disabled and turned into quickchat - not necessarily because FFXIV players are so much worse in toxicity, but more probably because of japanese development standards doing this as a preventative measure.
As for "there are more people playing casual than ranked", this has very little to do with toxicity and everything else with the systems surrounding it. I do not like the implication that social behaviour is a primary reason here.
PvP, within the scope of PvE-centric MMOs, may be a side activity, but has generally been the most standard side activity to be considered and worked on. Story is a baseline, crafting is a means to an end that some people may enjoy as an activity, housing is limited to availability and funds - raiding is arguably "the" main drive here.
PvP being seen as a mere side activity comes from two sides - word of mouth advertisement from other players, that it is awful / forgotten / just side content, devaluing one's opinion and interest before they even touched PvP in the first place; and a variety of rather questionable decisions of how they tried to make PvP approachable and more importantly "worth your time" (or rather failing to do so, despite the miniscule steps required to pull it off), a subject I could dedicate a separate thread to.
That said, Valence did not say that at all, even in the unshortened version. Valence made comments on the state of Ranked CC on how fast it dies out, the most likely chances to have enough games to play Ranked within a season and his experience with how much of a disaster it has been based on the timing of everything else essentially siphoning players away from it. There is no statement whatsoever why it should change, nor any thought why decisions made around Ranked CC are more important "than the broader game experience", which is also fairly odd to suggest given PvP changes can be made that do NOT impact the broader game, this isn't zero-sum game development.
Ranked PvP has been a malnourished carcass due to terrible design decisions to make the mode even remotely worth playing. We have an equivalent in PvE regarding this - Criterion. Its' rewards were absolutely underwhelming to the point that active parties died out about the same rate Ranked dies out. Criterion had very little replay value and no interaction with the main gearing system (which has been criticized for a while now) and its rewards were incredibly paltry.
Ranked PvP, pre Crystalline Conflict, at least had people fighting tooth and nail for the Top 100 rewards, because they were actually desirable and worth fighting for. This however was also a time when casual rewards were absolutely lacking (lack of Battle Pass, cool things outside of wolfmark vendor, etc) and the one-of-each-role queue system made The Feast incredibly difficult to approach and learn.
Ranked PvP, post Crystalline Conflict (6.1), has seen a full revision to the reward structure, with GREAT benefits to the casually available items, but at full neglect to Ranked rewarding you anything of desire (which would NOT need to be a FOMO reward, mind you). Ranked PvP went down the same path of Criterion, where the average player sees absolutely nothing worth in it to spend time on it. This isn't a "PvP is a side activity" thing either because they've made side activities with GREAT rewards multiple times - Ishgard Restoration and Cosmic Exploration on the crafting side for example.
It also currently suffers from a death spiral of "nothing interesting for me here before reaching a rank that is out of my skill potential -> I leave -> queue times get too long for me to care while casual has more games -> I leave -> repeat". Crystalline Conflict is fun - but queue times aren't. I do not like sitting between 5-30min for a game of ANYTHING, much less if the result of me doing so does not offer any tangible rewards afterwards.
To say "Ranked is dying for the same reasons it always has" means you actually do not look at the state off things with any analytical thought on objectively distinct designs on its User Experience and reward systems, but rather regurgitate hear-say of what is mostly anecdotal to begin with. This is incredibly disingenuous.