Guys, you all deserve a cookie... ONE cookie and one cookie only for each one of you. Here!
Now be happy and hug. *-*
Stats don't make such a huge difference, as long as you're not completely wastnig them, while yes you will do more damage if you choose certain stats over others as they provide a better bonus for your class and possible playstyle (the latter doesn't apply anymore really, not to such a simple game anyway), if you don't specifically favor any you won't lose THAT much damage neither.
The biggest damage loss you can have will come from how you play your class, not for what piece of gear you're wearing. (obviously there's a big gap between ilvl 50 and 90, but you should understand what I mean). Damage difference between a full BiS geared and another 90 decently geared is not that big if both know how to play their class. As long as you don't throw away your stat points into wasted stats (two big noticeable stats that go in a waste is ACC over the cap, and most content has a very low cap except Coil, and piety, as it can be overcome by smart play and efficient mana management past certain point, vitality could be seen as another wasted stat if you already have enough to ensure your survival).
Anyway.
What he said is all wrong, the delay will always be there because it's given by the time the information takes to travel from your client to their server.
What can be done is implement countermeasure to make this time not reflect any negative impact in your gameplay. But that's a whole different than there not being a delay.
Regardless, what he said is still wrong because your speed is there, while is true that delays make haste a little less beneficial, this doesn't affect anymore as it may have 15 years or more ago. Either way, even if the delay interfered, you sending a command .25s earlier would still be .25 seconds earlier even if it gets delayed, because the delay will apply to both cases, so it's just a flat out base increase.
Anyway, his point still remains that spell speed is a rather weak stat, but not because of the reasons he gave. However, crit rating will not add any decent amount of crit neither.
It's up to you whether you wanna attack that little bit faster or crit 3 more times out of 100, or 5 more... I don't have the exact numbers. But they are not that unbalanced to make neither stat completely useless. Just not as good maybe.