I see this opinion all the time, but I completely disagree with it. The weapon summoning and warping is the basis for one of the most interesting combat systems I've seen in a long time. As well as the fixed party with people who have been friends for many years, and the road trip style game.
Every time I see this opinion it feels like the person doesn't care about anything other than the plot in a game. Like they're thinking "there will be battles anyway, it's FF, who cares". For as much as it differs from the original concept, FFXV is still the game it is because of that concept, without a doubt. They're not just keeping the name and character designs, they're keeping many core concepts, and even improving on some of them. Like, for example, I don't think anyone saw the Versus CGI/Advent Children style battles that were promised in that 2011 trailer, but I just chose to balee because Nomura makes great games with fun combat, so there's no reason to worry about its quality, but it's undeniable that the current battle system does a lot more to keep that promise than what we've seen before (including, and especially, from Tabata's own Episode Duscae combat).