Temperature depends on current flowing through it, and voltage across it, and just how big a heatsink you have it attached to. Nothing else, and these are all the same for all manufacturers devices within small limits. It has to dissipate the power somehow, and there is no difference between brands as to how that is made, it is V differential times I.
However, there are differences in a generic "7805" from different manufacturers, many are limited in how much power they can dissipate, simply from the method used to attach the die inside to the copper tab, and others are limited in the maximum input voltage they can handle ( often under 12V for some lesser known manufacturers) and in the action they have under overcurrent conditions, some limit to a maximum current, some fold back to a lower current and some just blow up with a shorted output. As well they often have different behaviour when they get too hot, some work correctly and shut down, others just keep on cooking till they go short circuit input to output and others just blow up after going short circuit .
All this is mentioned in the datasheets, so best is to buy reputable manufacturer ones from a reputable dealer, not a low feedback new eBay account seller with a some "ST", "Onsemi", "NXP" or other brand part that most likely is either a counterfeit, reject or otherwise mostly defective part.
As to how to kill them it is simple. apply too much differential voltage ( ie, 35V input and want 5v output at 0.2A which will overheat any of them), draw too much current ( 1.5A from a 1A part with 10V input for long period) or overheat them ( 5V at 1A, input 12V, with a heatsink of 20C/W rating which is most small clip on ones) so that the chip runs at over 150C inside the package, or apply a voltage to the output and nothing to the input and leave the 3 diodes recommended in the datasheet out. Reverse voltage also kills them fast.