Woo, you sound just like me. I recall a conversation in the canteen with a colleague recently where I said something along the lines of "... this place is so mediocre ... there has to be something better ..." and she replied with "well its just a job, you have to work somewhere, there are plenty of places worse".

She has clearly decided to settle!

I also agree with the less ambitious people doing well - I liken it to Seth Godin's book The Dip - those people are willing to lean into the organisation and just settle for its way. The more ambitious can sometimes see just how wrong things are and lean against it, hence doing badly in the company. If you are going to do well in a big corporation, you have to learn to play by its rules and settle unfortunately ... I haven't done that yet, but its a daily struggle!