That guy is uh, pretty biased towards D2.
Not that he's wrong, or right.
I think he's offering a fair POV to give D2 a chance, I think too much are people expecting D1 meta to instantly carry over to D2. We won't know until you are at the end game, and since we aren't, what we have currently is still at least imo (since I like Halo 5) I think it's great.
It just feels weird and different. D1 towards the end, lets say control, I felt I was good enough to make a huge difference to the outcome. I'd get in there and grind grind grind. Capture points, fight for points, weaken enemies for others to clean up. Spam everything I could, grenades constantly, I'd usually finish first or 2nd in scoring. i felt like 2nd with more kills was better TBH, I'd rather go 24-16 than 18-6 in a way, because that meant I was mixing it up and fighting over those flags constantly. Of course you get games where your team was just outmatched. It happens. But I felt like I made a big difference in helping us win if we did. I could physically feel the satisfying grind.
You are making a big difference in D1 or D2, just how you go about making a big difference is what has changed. Your decision making changes, what you do and how you approach certain situations are now different. Where previously with the right gear, load out, and abilities, you could use your abilities to nearly bend any situation to your will.
With D2, currently as we know it, like Halo, you have limited ability to force the outcome of a situation in a head on head situation, so flanking, retreating and picking when and where to fight, with which weapons is going to be what makes you better or worse than other players. Are you feeding the other team by running in solo? or are you working together? If you're working together do you know which flanks to cover and which ones not to?
It's not as simple as people moving as a unit and murdering everything, it doesn't quite work like that.
The biggest difference imo, is that with Halo 5, and other FPS games, I'm trying to coral players into area where they have limited cover, I have cover, and I have the right weapon for the job.
In D1, if I had the abilities, I could toss it in and run in head first blow shit up, and if I succeeded the cool downs would pop, and I could chain them. That's quite different.
TLDR; it's not a terrible thing that players have to learn to play both defence and offence, many would argue that this increases the skill ceiling. D1 was mainly just offence.
Also supers are currently such in D2 that they're just a steamroll mechanic. I've had good games that we won and I got good kills that I never got my super. You're only going to get if you're rolling the other teamn, which is just going to make it even more of a rout when the team ahead by a lot all gets supers and the team behind a lot doesn't. That's a real obvious issue.
You're going to run into situations where supers will turn the tide, 3 games in a row of control supers at the end managed to turn the game from just lost, to just win. Way too early to judge still on this one imo.