Aside from gameplay complaints, LoS has earned more criticism than the others.
For a very vocal sect of the fanbase, sure. But back in the day there was an equal amount of complaint and dissatisfaction over the N64 Vanias and the PS2 titles for various reasons both technical and artistic. IMO nothing's really changed with LoS other than the fact that we are all raging over the plot details now more than the gameplay itself (ironic, considering how often it is stated what little role story plays in the fun factor of most CV games of the past). Everytime a new 3D Vania comes down the pipeline, a whole new generation of haters is born. I think those of us that don't like LoS want it to
seem like it's the worst 3D Vania to date, but that's just a forced projection of opinion. You can't discount a section of the fanbase that found it felt very much like a CV game (and there are quite a few of us that did) just because another section of the fanbase did not.
I'm not saying this to counter any dissent posted against LoS, but to give a bit of perspective regarding this whole notion that LoS is a sure sign of the coming death of Castlevania. I think that that's a bit of an alarmist statement to make. I had alot more concerns for the direction of this franchise following LoI than I did with LoS, but that's probably also because of the level of expectations I had placed on that game before its release...along with the inevitable disappointment of it ending up nothing like I had hoped or expected it to be. I'd imagine this is the same sentiment as of alot of people who mistakenly put too much stake in LoS before its release, but from experience I can tell you....life, and Castlevania, will go on.
Truth be told, I have more concerns about how Konami is handling its 2D games as of late than its 3D series. THAT'S where I feel the disrespect for the fans of this franchise is really being generated. They are leaving TONS of potential on the table IMO, and it's baffling as to why that is. The budget for a decent HD 2D game can't be more than for that of a full fledged 3D title these days. Apparently someone at the top of the totem pole is convinced that 2D titles can't do well on a home console anymore. That....is worrisome.