well if tyres squeal when they are overdriven than they are wearing more than when they squeal at optimum angle and speed .. I think
at least that is how I imagine it should work .. something like when on real track when you are too fast with too much angle your tyres start "jumping" over side walls (if it makes sense) and you get nice sound and "force feedback" in your wheel (and body) telling you you are not really helping yourself, just killing tyres ... that pariticular FFB effect is missing in AC but I guess setting tyre squeal to that level could replace it ..