There really is no point making a judgement on the merits of crt vs lcd through side by side photos. For a start, not all crt displays and lcd monitors are created equal. With both technologies, you will find some displays with amazing blacks and some that suck. The 40" pioneer 4:3 plasma monitors, for example, have terrible blacks but the Pioneer Kuro tv's have blacks that have only been beaten by OLED tv's.
Similarly, there are a number of CRT displays (mostly made by Sony) that have great blacks. Home theater fans still buy Sony G90 crt projectors for their amazing contrast. 240p games through Svideo on my Sony Trinitron crt tv have decent blacks and a overall good image quality once I have adjusted the color balance on my jrok encoder.
The real advantage of crt over any other technology for gaming,is their ability to switch resolutions. Lcd and plasma displays have a fixed pixel pitch and scale every other resolution to fit. Scaling makes 2d graphics look terrible because the scalers inside most tv's are terrible. You really need an external scaler to make old games look ok.
Because CRT's don't have a fixed pixel pitch or a native resolution, you can play an old 320 x 240 game, followed by a 256 x 240 and then a 640 x 480 game and they can all look perfect. If you are going to use an lcd or plasma for classic gaming, you should ideally look for a 480p one so you can have 240 lines plus 240 black ones as simulated scanlines. This is why those old 40" 4:3 plasma monitors are in demand. They have a native 480p pitch and are the largest 4:3 flatscreens available.
Incidentally, if you are choosing between an lcd monitor vs an lcd tv then perhaps the tv might have an advantage for older games as it will probably accept a 480i 15khz signal. It will still upscale it but at least it will display something. My lcd monitors normally just say "out of range" when I try old 15khz games. This will only apply to older lcd tv's though. I hear than some lcd tv's like Samsung panels, won't accept old game console signals.
I currently use a 25" trisync crt arcade monitor for old games and a 24" 16:9 Sony playstation monitor for newer games. The 24" led playstation monitor is the best I have seen for old games on an lcd monitor. Even though it is a 1080p panel, they managed to display 240p games (at 120hz) without adding too many jagged edges. They have HDMI and component inputs too. They are also 3d. 240p games on my other 1080p lcd monitors look like a pixelated mess.