They still have issues with problems like this actually, and I use all the frontier models from all the major labs, so it's not solved.
Me: What about in rrorooroororororrrrrrorrororororororrrorooorrorroror
Opus 5.5: There are 29 r's in that string.
There are 30rs in the string. If you want I have a screenshot.
The reality is this, the models "think" in tokens, not in letters, so they can easily make mistakes like this and it's very hard to stop these kind of dumb mistakes happening. So yes, frontier intelligence at work.
You're also splittin hairs if you argue Opus 5.5 isnt "frontier".
https://artificialanalysis.ai/models
Artificial Analysis considers Opus 5.5 to be the best current model, yes better than Fable.