No, it's not. Having worked with the Jetson platform extensively, the TK1 was equivalent to a 5422 (because they're both built on the vanilla A15 architecture). However, the TX1 and TX2 ("Denver" cores) are closer to (though, still slighty behind) the current SD 835:
I'll correct to "comparable", as it's more appropriate.
However, it's not a "clearcut no" or "very powerful in comparison", due to the number of cores (no doubt about the GPU, I had made this explicit in the parent post).
I've run the Phoronix test suite (which uses a set of real-world applications)[⁰], and, excluding the outliars for both parts (Redis/OpenSSL), we're talking about 10 to 40% advantage for the TX1, and little more for the TX2; XU4 has even the edge in one case.
They're definitely faster for the majority of use cases, however, I wouldn't classify them as "very powerful in comparison", at least, when considering the performance of an RPi 3B.
The TX2 is a dual-core chip (ignoring the 4 "littles" since they're unused in benchmarks). The 5422 is a quad core. And even then, it's outperforming the 5422 by a decent margin in most tests. Even c-ray, an intrinsically multithreaded application is close.
So you're correct, they're "comparable" in that if you take twice as many 40%-as-powerful cores, you might shrink the gap. But for any fundamentally single threaded tasks, a massive gap exists. And if/when you leverage the GPU (which can't be ignored, despite your handwaving), it becomes a canyon.
https://www.youtube.com/watch?v=l6y4atVl-mc
And when it comes to GPU compute, it's much more powerful than all the alternatives.