True but only if you understand what exceeding a specification means. It does not necessarily mean having a higher number against a specification. For example when looking at the collector / emitter saturation voltage a lower number here is better.
Yes. Also it bears mention, that some circuits are designed in such a way that exceeding the specifications in what would ordinarily be a good way, will lead to failure. Magic numbers and sneaky tricks, if you like. It's rare, but it happens. So you might see, for example, a circuit that has a flaky design, but parts were swapped in and out until it worked. I have seen cases where we had to use such and such a part only from a certain manufacturer, because of this. Generally, it is because the circuit lacks compensatory measures like feedback. An example would be a common emitter amplifier stage that is DC biased by feeding current to the base with only one resistor (and emitter grounded). The DC bias then depends on gain and other factors like temperature, etc. Obviously, you cannot replace it with a transistor with a "better" gain, because it will upset the bias. You need one with the same gain.
Thus, you should know some electronics before replacing a transistor. But there's a lot of wishful thinking going around these days, it seems. Also a lot of stuff on the market with absolutely pathetic documentation and/or sketchy specs.