These simulations aren't Instagram gimmicks and are often used by pro photographers. If you'd rather not muck around in Lightroom, they'll give you a great, consistent look, in-camera.
If you'd rather shoot with RAW and apply your own looks or treatments, Fujifilm's 14-bit RAW files give you plenty of data to work with. Below ISO 6400 or so, you can dig into shadows to find detail, and pull extra notes out of overly bright skies.
I'll try to make it extra clear: The X-Pro3 isn't designed for video. You can't see the rear screen without flipping it down, and it won't go down more than 90 degrees when mounted on a tripod or gimbal. That issue also makes it impossible to vlog with it, too. And remember that there's no HDMI port, so you won't be able to use an external display, either. Finally, unlike the X-T3, it lacks 10-bit video recording.
It's not all bad, though. If you're willing to use the EVF or OVF, it does deliver full-sensor 4K with downsampling, focus peaking and even F-Log capability. That's enough to let you shoot some good-looking video in a pinch. You'll get very sharp 4K video and accurate colors, and I had some fun shooting video with the Acros black and white and Velvia film simulations, too. In fact, if I were shooting video with this camera, I'd probably use the Acros and Eterna simulations all the time and just not do any color correction.
Still, there's no point in getting this camera if you do any serious amount of video. For that, just get the X-T3, which is the best APS-C camera for video right now -- and cheaper, too. On top of that, if you're also into street photography as well, the X-T3 is an excellent choice as it handles well and has the same sensor as the X-Pro3.
It's hard to assign a score to a camera like this because it's clearly for a very narrow group of buyers. It has very unique features, like the optical viewfinder, not found on any other cameras. Nevertheless, the X-Pro3 is an expensive camera, so I'm going to try to compare it as fairly as possible.
It's not a very practical camera. While the odd rear display does help you concentrate, you could argue that you'd get nearly the same thing by buying an X-T3 and just turning the rear display off. The optical viewfinder might be a bit faster, but it would take a lot of practice to really master it. As for video, it's just not very practical on the X-Pro3.
Dispassionate scoring aside, I had a lot of fun using this camera, and it's refreshing to see that Fujifilm is trying to do something different rather than just ticking the usual specification boxes. In the end, it actually succeeds. The elegant rangefinder design, wonky rear display and OVF worked as advertised. By removing distractions, the X-Pro3 forced me to focus on taking pictures. And thanks to Fujifilm's color science and simulations, I was very happy with the photos I took.
For most folks, however, I'd recommend the X-T3, or if you want to go full frame, get Sony's A7 III for around the same price. However, if you're looking for a camera like this and have $1,800, you probably already want it -- and no review is going to change your mind.