When you zoom into an Illustrator file that contains vector elements and/or type, then every time your artwork will be rasterized at the highest possible resolution for display on the (pixelbased) monitor. So even when you're zoomed in at 60000% the edges will be crisp.
It Photoshop your artwork gets rasterized at the file's resolution. There is no dynamic rasterization. So when you zoom in, all that happens is: the pixels get bigger. Smart objects might still have higher resolution or be vector based content. But they only get resampled when you scale them. After scaling they are rasterized according to the document's resolution.
An Illustrator file does not have a resolution. Some of its contents may be raster elements and those have a resolution, but not the file itself.
When you export a JPEG or PNG you set the resolution on export and it's fixed then. It won't ever look as crisp as the live rendering inside Illustrator.