Well the expansions changed the formula a lot. In ARR the areas were smaller and split into pieces and we had 3 regions, so they had a lot more beast tribes to explain. We also had more dungeons due to the sheer amount of levels. Thus, from ARR to Heavensward we lost things. Less levels, less dungeons, less beast tribes. Sidequest dungeons continued to reduce over time.

But everything other than that remained the same or increased, except in Shadowbringers where they seemed to cut Hildibrand (despite explaining how they get to The First in Stormblood) and an Ultimate and Allied tribe quest due to covid.

I am not aware of them skipping a tribe in Stormblood. There were 3 just like in Heavensward, including one in The Fringes.

Given their whole strict formula it's hard to say they cut things that were previously planned. But we could say they "intentionally didn't continue things", such as grand company ranks and dungeons or a deep dungeon in Shadowbringers.