I obviously can’t speak to your experience. But in mine, we had a lot of “SME” people who in reality sucked. They were regarded highly, but once you stuck a real problem in front of them they’d just claim it couldn’t be done, it was a system limitation. Which was complete bu-----t. Once we brought in a few contractors and new hires, they completed things that were “impossible”. Most people went on believing the SMEs were good, but management found out their lack of skill and that they would take credit for the success of a project when it really had nothing to do with their “expert” knowledge. This largely came up when it was time for PDS reviews, and there was conflicting information. So they got PIPed finally. A lot of these people were older, because we promote people based on age and we don’t have SMEs who are 25, we only have them when they are 40 etc.
If you just do the job that was assigned to you, and make 1-2 small improvements to the process each year, you’ll be just fine. If you want to reach the higher positions, you’ll make 3-4 bigger improvements. It’s really not a complicated system. Now if you want to hit executive level ok sure get a sponsor and BS your way to the top. But it’s really not that hard to avoid PIP and have a good career here.