One thing I'm not sure has been mentioned is that LCDs always have a fixed resolution. It can simulate different lower resolutions by lighting up more pixel area but the further away you get from its Native resolution, the less sharp and pixelated the image becomes. If you have an LCD TV capable of 1080P Resolution, the image quality of a 720P broadcast will look worse than a LCD TV that is only capable of 720P. CRTs on the other hand can project a perfect image at an exact resolution. Low Res images in particular look far better on a large CRT, then a fixed high res LCD.
The only real advantage of LCDs it's far more compact than CRTs. Today people are obsessed with really large Televisions of 50+ inches. A 50 inch CRT would take up most of the living room in some cases and weigh an ungodly amount because of the large Tube needed to project a large image. So LCDs are more practical in these cases.
It's also not true that CRTs cannot have a resolution as high as LCDs. The only reason you haven't seen CRTs with Resolutions as high as LCD of today is because they just aren't making CRTs anymore. There is not the same demand for them anymore and the industry is pushing slimmer technologies.
Let's look at the historical advantages of a CRT over an LCD:
1) Authentic look: scanlines, shadowmask, bloom, and so on.
2) Motion smoothness: ability to run at the original game's refresh rate without stuttering or hiccups.
3) Responsiveness: virtually no input lag.
4) Low persistence: very little motion blur.
I'd argue #1, #2, and #3 are basically solved problems at this point. See below for more details about the Timothy Lottes shader. G-Sync solved #2. G-Sync also basically solved #3, because anything you saved by using an CRT is compensated for by the fact that G-Sync has less input lag than running with V-Sync, which you need to do on a CRT. What's really awesome about G-Sync, too, is that you can actually use Calamity's frame delay patch on a G-Sync monitor without visual anomalies to get even more responsiveness out of it. #4 really isn't a solved problem yet. There's no flat panel low persistence option that doesn't reduce color quality yet, but with a 144hz LCD with a 1ms response time, motion blur on all but the fastest scrolling games (Sonic) is pretty subtle.
The more resolution you have, the BETTER it looks and the BETTER it can simulate looking like a CRT if that's what you're after. As far as static image quality goes, it's a solved problem. It's been done. Timothy Lottes's CRT shader looks better than any CRT I've ever seen in my life, and I've seen dozens of arcade and consumer monitors.
https://436e85e1-a-62cb3a1a-s-sites.googlegroups.com/site/bigbluefrontend/sfa.pngI own a Wells Gardner and Nanao arcade monitor, and this looks better. You simply cannot get an image that pristine and uniform on a CRT. The only real advantages CRTs have at this point are on the motion blur front (they don't even really win on responsiveness anymore when compared to OLED).
Nobody said that CRTs cannot be higher resolution. I said that CRTs will never be higher resolution. The reality is that no one will ever make a 3840x2160 CRT. It'll never happen. It does matter if it's theoretically possible. It won't happen, so who cares? It's over.
LCDs have better image uniformity, and they're more reliable. When you have enough resolution, fixed resolutions are a GOOD thing, especially for a MAME cabinet, because you don't want to see ugly resolution transitions every time you launch another game. LCDs are easier on the eyes than CRTs. I know many people who can't stand the flickery appearance of a <=60hz CRT.
The real problem with a lot of these comparisons is that people are comparing Dell LCDs from 2001 that they found in a dumpster to the very best arcade CRT they've ever seen. I challenge anyone to use an ROG Swift LCD with a properly configured SDLMAME and tell me that it doesn't blow you away. A 1ms 144hz LCD doesn't really have enough motion blur to offset its advantages over a CRT. Yes, if you have some crappy 10 year old panel with 12ms response time that runs at 60hz, sure. That's awful compared to a CRT. That simply isn't what I'm talking about, though.
A lot of this really depends on what your needs/goals are. If you're going to actually buy an original PCB and have a cabinet dedicated to a single game where you can gobble your knobs and tweak your potentiometers perfectly for that one single game and want everything to be original and authentic, I can totally see using a CRT.
If you're going to build a MAME cabinet to actually, you know, play games for fun, a good modern LCD really is the better option overall. You can't even play the new Mortal Kombat or Street Fighter IV on a CRT properly. I mean, just look at those cabinets that are running Street Fighter IV on a CRT at 640x480. The laughable aliasing is far more offensive than the analog on an LCD. At least the CRT shader on an LCD actually looks good. What if you want to play a contemporary 2D game? A CRT bottlenecks what you can do in so many ways, and the few advantages it has at this point simply doesn't outweigh the advantages of a good LCD.