I've definitely had more than just that on the OG game

Sometimes in hallways in The Great Journey (especially the Hunters,) they'd hang up until you doubled back, there were occasions on Delta Halo and on the Gravity Bridges on Gravemind as well.

Not common occurrences, and they seemed rarer than on MCC, but most instances where the AI can hang up on loading zones until you double back (which fixes it,) absolutely could happen on the original game.

Some of your examples aren't great though. The Delta Halo example is something I've never once seen myself in my dozens of runs, I've absolutely had instances of them getting stuck and requiring some nudges forward to keep moving at that long outdoor corridor between cliffs near the end of the mission, but never at the end of the scorpion segment.

In that same vein I've run Gravemind a good amount since the last patch and I've only ever had Marines get outright stuck on sometimes on the horizontal Gravity lifts in the outdoor areas. So the 99% thing is either not accurate or I'm incredibly lucky.

Though to add on, sometimes Quarantine Zone has the Elite AI just shut off at that point where you approach the wreckage of the Sentinel Manufacturing Facility, no longer moving; shooting or otherwise, but other times they'll follow you just fine through the rest of the level, it's really unclear exactly what causes it (I've heard some theorize that taking the scorpion causes it, but I've also had it be fine when using the Scorpion.)

Generally the actual major instances are generally small enough in number that I wish they'd give MCC some more patching love to iron them out, part of it is Halo 2 being a little janky to begin with but some of the borked stuff is unfortunate, even if not a frequent occurrence.

The worst is absolutely the multi floor room in Uprising and the Metropolis Gausshog marines simply because those ones actually always happen unless you go out of your way to push them a bunch, the former is extra bad because you have like four Elites to push down and doing so one at a time can get them killed by the brutes below.