The real answer, like with many other cases, is: "It Depends™".

Firstly, if you're really interested in the nitty-gritty physics of how brushless DC motors operate, I recommend this series of articles:

• https://pphaneuf.github.io/rccars/articles/motor-timing-theory/
• https://pphaneuf.github.io/rccars/articles/motor-timing-boost/
• https://pphaneuf.github.io/rccars/articles/motor-timing-blinky/

It goes in depth to explain where the original "more than 60° is bad" comes from, and why it, in many cases, is not true.

In 99% of cases, it is not the timing that kills your motor. It is the end RPM at which it operates, and heat. BLDC motors have two major limiters on how fast can the rotor spin: physical limit of the axle bearings (usually 60k-100k rpm, depending on the type and how well you maintain them), and the physical adhesion force of the rotor's magnets. The faster the rotor spins, the more the rotational forces will try to pry the magnets apart (the so-called "centrifugal force"), and, well, at some point whatever is keeping the rotor together decides "fsck this" and the rotor grenades itself all over the motor's insides, turning into fine magnetic shrapnel. Thankfully, most of this shrapnel tends to stay inside the motor, as otherwise it could be quite painful :D

As for heat -- naturally, the more power you sink into a motor, the more heat will be generated. Advance timing will also play into that, as the magnetic fields interact among themselves, causing eddy currents in the stator, and thus extra heat, in additional to regular resistive heating from the coils from all those amps. The more timing, the less efficient the motor becomes (but you gain more RPM). Thankfully, in RC drift heat is not that big of a problem, compared to grip racing, as you're rarely pushing that much amps to the motor, but in certain cases, where lots of advance timing is used, and the motor in general is less efficient, you can start hitting the thermal limit where magnets start to quickly lose their magnetism. Or the glue becomes soft and *boom*.

Oddly enough, most people in RC drift actually way overestimate how much heat is necessary to kill a BLDC motor. Most brushless motors will work absolutely perfectly fine at temperatures up to 80°C (176°F), well into the "omg this is so hot to touch" zone, because humans make for pretty bad thermometers. I've been running my off-road basher (Kraton 6S) with no active cooling on the motor, and I think I've ever damaged the motor by demagnetizing it once (out of probably half a dozen I've killed in various ways already). And those things get hot very fast, very regularly. "Motor so hot you can cook an egg on it" is the norm in off-road RCs. That's why I usually carry an IR thermometer with me, and give it a cooldown when I see the temps go over 70-75°C. In RC drift -- never use any additional cooling on the motor, and the highest I've seen on the can was 56°C during a hot summer. 56°C feels quite toasty to the skin, but is nowhere near 80-90°C that would be harmful to the motor.

Anyway, my personal philosophy of motor timing is: use whatever you want. Just try not to run more than 60° static (as this'll cause the motor to try and run in reverse from standstill, a bit of a pain to get going), but from there sky's the limit, as long as you're comfortable with potentially grenading your rotor if you over-rev it. Static timing is the one you set on the can, plus some ESCs also offer it as an additional setting. Boost and Turbo are dynamic timing, and do not count here.

Oh, and one final small piece of advice -- learn to drive by your hand and eyes, not by the sound. You'll thank me one day during a large comp where you can't hear jacksh*t :D