I see what you're saying, and I fully agree that alot of changes have come into the game that were required to freshen it up. But I disagree when you say that RE hasn't stayed true to it's roots. It is still essentially the same game. You're running around, killing zombies in a weird and unknown, haunting location.
I don't think you understand the changes are HUGE in terms of gameplay, it's not the same roots as the original games. You can apply the same answer to Splinter Cell. You're not working for the original organisation likewise in RE, but you've got to solve a conspiracy like which was in Chaos Theory before bad things happen, you simply don't use light and shadow mechanic and use the stealth suit, it's more outdoors. RE was more indoors it changed to more outdoors many complain about this, but if I bring this change up about RE it's still the roots, you say it's the same game? That doesn't make sence to me, the changes done to RE are like ones done to SC, if you've followed the series RE 4 plays nothing like the previous games in terms of gameplay mechanics, and this is the main complaint of SC there is no light and shadow mechanic, so how is RE any different to RE fans complaining there is no fixed camera? It's no different.

Many of complaints have been well, you're not wearing the stealth suit, not wearing trifocals, not working for 3rd Echelon, shouldn't be called Splinter Cell. Now in RE same happens S.T.A.R.S are disbanded, there is no Umbrella, formula which has been in previous games is gone poof, this is acceptble in RE but not for SC, please explain the contradiction? Also you say is true to the roots in what way, when it's all changed? am I missing something here?

They care that you're taking Sam out of the role that the whole franchise is based around. They want to see Sam as the invisible infiltrator, who stalks, takes his time, draws on his experience, prepares and then strikes quickly and effectively.
Who says you can't do this? The whole definition of stealth is to go unnoticed, the game is based around stealth, put action in there to interogate or neutralise/incapictate. You say it draws on his experience, you know he worked in the navy SEALS? They are trained in counter-terrorism, which means dressing up in civvy clothes for recon/surveilance could be anything here builders, businessmen, traffic wardens etc... who would think they where Special Forces with an MP5K under their shirt? They have knowledge in demolitions and explosives, hostage rescue and many other skills such as Escape and Evade , which he is doing. It's not simply sit in the shadows, unfortuantely the sun comes out during the day which means agents in real life agents have to improvise, and to be quite frank, why have an Agent like Fisher if a normal MI5/FBI agent can do a dual role but Fisher can only do night time?

I don't agree with anyone that thinks that Ubisoft had to take him out of that role to "freshen" up the title. That's a ridiculous claim that really doesn't place any faith in Ubisoft's potential as a game developer. But I do agree that shadows were just a simple cool way of providing a stealth mechanic, and that it has lost it's challenge.
They didn't have to take him out of the role you're right, but they did need to freshen up the title, use new concepts and new gameplay to make the game innovative and inspire gamers not only through gameplay but story. The 4 games are just little upgrades from each other while fun are now unchallenging, while maybe fun to the super duper die hard, to many people it's monotonous now, and we do need to see some progression and variety not these black looking missions.

I'm pretty sure that if the Resident Evil developers had made all of those changes to the game, while at the same time outfitting Leon in some chainmail and pitting him against some goblins in Hyrule, then they weren't going to be as supportive as they are. (fairly drastic change I know, but you get the idea)
It's funny you say that, at the end of the first 2nd and 3rd game games, you can change the costumes to different ones that look stupidly unreal, think there is a tomb raider one for Jill. I mean to put it into perspective for you, there is a guy in the second game, in the mini-game called "hunk" and the seconady character is called tofu. I kid you not, you can play as a tofu bar it's injected humor by the devs, when he gets bit he goes "how you do there?" can watch Here