I'd agree it is fairly profitable for people to even split the area but with decent kill speed even one player soloing it who can do all the panthers in two pulls quickly will be waiting for respawn. With two it becomes a lot of sitting around - and this boredom is I'm sure what provokes some of the toxic behavior. A "good" grinding spot or source of income is completely relative to one's expectations though. When I first discovered panthers - actually I stumbled upon them in my second week of play, not even max level - I was thrilled to see so many melee enemies hanging out together - any veteran MMO player knows what that means in terms of xp and money. I made good money killing them solo or splitting the zone for some time and made some friends that way. But that value may not be good enough to be even close to "best". No general disagreement that they are good even with two - just in general it comes down to one's expectations and I believe most go to the zone hoping to have it to themselves which has become increasingly rare.
As far as thinly veiled personal attacks, it's common for people obsessed with panthers as many believe the panthers truly belong to them or they are the "best" source of money. Typical behavior in MMO's in my experience with players competing even over PvE content. If your comment was in reference to my most recent post - I have nothing further to say to the person who made that comment that provoked my response. In general, unprovoked responses (my post that he quoted was just about panthers in general, I would be just fine if they deleted that pack of mobs entirely) like this are just the kind of toxic behavior I am discussing. Just noting that you are correct that there are a lot of bitter comments any time panthers come up. I think all but one of my harassment tickets I sent in were due to panther drama/harassment by players verbally out there. I moved on from panthers other than as a fun way to get levels on occasion for an off spec.
As far as comments about "very few" being able to kill all the panthers quickly - I'd say nearly anyone I have seen out there can do that. The question is how quickly. When the venom would show up is when you would pull faster than another player out there (75%-100% of the zone in one pull is easy for a good cow build as you have damage immunity to panthers with the right mods and insane movement speed) and they would ask you to leave, if you didn't want to then the next thing was them trying to "tag" or "loot" (old bug) your mobs. It was always kind of funny to watch and produced probably the most toxic behavior I have seen in this game. The comments you mention in this thread are pretty much a result of such behavior. I haven't played in awhile so I wouldn't even know who to address with veiled attacks. Literally the only people I remember are guildmates. We all can agree that provocative posts such as that one are just the kind of toxic behavior that pollutes a good discussion.
I prefer an alternate zone where with proper vendoring I make more per hour. There is also zero competition in it so you can relax and be sure that no one is going to come out and start messing with you and when you refuse to leave begin name calling. THAT zone (and I'm sure there are a few other spots) was what I referenced when I implied "very few can solo it". Panthers could be soloed by anyone who knows how to properly kite. I think I was doing so at level 40 or 50 with fire/ice by tagging, freezing, and nuking. There are many variations of this strategy (BChemistry is fine too). Archery can probably solo it all in one pull with no second spec at level 20 (joke).
TLDR: Panthers good, troll/venom comments are bad, discussion good, panthers are easy.