Titan Z in its full glory was Tesla K80 & shipped with 24GB RAM in 2014.
Titan RTX had 24 ramsies in 2018.
If RAM is what you need, and don’t wanna download it, you “can” buy an H100 with 80GB RAM (2022, Hopper architecture), they sell it on a PCI card too.
It costs some real cash-moneys tho.
In the realm of still imaginable GPU prices, Quadro usually offered more RAM, eg currently sold is the RTX 6000 Ada, comes with 48 gigirammers.
On consumer gaming cards nVidia has need horrible with RAM for a few gens now, I dont care about AI (on my desktop I use it once per year & on my servers & don’t even run it on GPUs bcs of how little I need it), def not enough gRAM for gaming imho, need some gigs as buffer for other shit.
I know there have been non gaming GPUs with so much VRAM, but that’s beside the point.
Titan is considered consumer, Quadro workstation, Tesla enterprise/datacentre.
I didn’t give it much thought, but I would consider AI (that needs more than low- or mid-consumer vRAM) the domain of Quadro.