Short answer: no. You cannot generalize that higher sensitivity speakers paired with a low powered amplifier is equivalent to a high powered amp and low sensitivity speakers at a given sound pressure level. It depends on the quality of the amps and speakers. If you take an X brand amplifier line of two different wpc ratings and match them with speakers with different sensitivities and listen at the same SPL, then you will be essentially hearing the differences of the speakers - assuming that the amplifiers of the same line are very similar sounding and everything else equal. And overall speaker performance goes beyond, and not solely dependent on, the sensitivity rating.
High sens speakers are not necessarily better - if they were, then everyone would own them. Everything in audio is a trade-off, and high sens speakers are no exception. They require, among other things, low mass drivers and high magnetic flux which introduce distortions that rigid high mass drivers in low sens speakers do not have. Also, by their very design, they may have to result to horn loading to reach down to the lower midrange to bass frequencies. So what is actually "louder" or more "dynamic" may be mostly the upper frequency range.
So, for a given cost, it's basically either louder with a relatively limited frequency response (especially in the low end) or softer with a wider frequency reponse.
High sens speakers are not necessarily better - if they were, then everyone would own them. Everything in audio is a trade-off, and high sens speakers are no exception. They require, among other things, low mass drivers and high magnetic flux which introduce distortions that rigid high mass drivers in low sens speakers do not have. Also, by their very design, they may have to result to horn loading to reach down to the lower midrange to bass frequencies. So what is actually "louder" or more "dynamic" may be mostly the upper frequency range.
So, for a given cost, it's basically either louder with a relatively limited frequency response (especially in the low end) or softer with a wider frequency reponse.