OT: Can't speak for other sentient species, should they exist. Jury is still out on us, that much seems certain.
However, our improving understanding over the last 15 years or so of just how rare and unlikely the development of complex life, much less complex life capable of forming differentiated tissues, was - just now reaching the more mainstream science outlets - suggests other less sensational solutions for the Fermi Paradox.
What we typically mean with "life on Earth" - namely the stuff we can see, effectively - represents just a tiny, tiny, tiny fraction of biodiversity on our planet, and all of it a rather late development. Simple life forms arose rather quickly after the formation of the oceans, as the evidence increasingly suggests, but it was another 2 billion years before complex single cells arose, and another 1.5 billion before those complex cells evolved into organisms. No differentiated tissues means no brain, no hands, no opposed thumbs. And simple life forms, despite their enormous head start, have never developed anything even beginning to approach the complexity of more complex life forms.
"Life on Earth," as we commonly refer to it, arose just 500 million years ago here. Primordial life, on the other hand, arose somewhere near 4000 million years ago. Not a trivial difference. And the mechanism for that step change from simple life to complex cells is apparently a single event. If that finding stands, it's a revolutionary insight.
TLDR: Expect to find simple life forms along the lines of bacteria and archaeans more or less everywhere conditions have been favorable for a few hundred million years. Fish? Amphibians? Oxygen producing plants? Not so much. Sentient beings? Once you get to complexity, we see lots of possibilities arise. The problem is getting to complexity.