Everything I've read suggests that you're very wrong, but in an age where people are publishing papers on plant cognition, maybe you're familiar with some interesting research. You suggest I "read a little wider". I've read philosophy on animal welfare and also about their biology. Where can I find a scientist who would suggest that all "complex life feels the urges it's driven by"? Because as I understand it, sentience is absolutely not universal to complex life. So I'm curious to read any serious academic who'd argue that sentience is present across all complex life.
I also never implied that all animals lack sentience. But I'm absolutely certain that betta fish wouldn't be able to recognize that you were ripping their heads off or something.