I don't agree. My first RE were 2, than I played 1 and 3, than Code:Veronica X with ps2. I also played the first Gun Survivor for ps1. I were just like you the first time I played RE4, than i came back to the other and I found the gameplay terrible, controls were much more slow and inneficient than i remembered. I played RE4 again and found that gameplay way better than the old one, with more freedom of moving. Nowadays I prefer the RE4 gameplay, I want to try it at Wii to know if Wii mote made it even better. I would prefer to say

People that don't like RE4 probably didn't tried the old one after. 

It is a poorly balanced game, too much inventory space and too much ammo.  If it was a complete shoot-em-up with 20 enemies rushing you non stop for 5 minutes at a time it would have been balanced.  Being a walking arsenal with what may as well have been infinite ammo and only fighting a half dozen slow moving enemies was rather pathetic.

Aside from that the story/characters are also terrible.  Take Leon for example.   Leon as we see him in RE2 and then in RE4 may as well be two completely different characters.  They are -nothing- alike.  They pretty much took the name and image of "Leon S Kennedy" and then wrote an entirely different character.  That is just lame.

For the story...fine no zombies, but could the game at least have anything to do with any RE game at least?  If you remove the name "Leon" from the character and replace Ada with some random tart, then snip about 20 seconds of audio from the game there is absolutely nothing that would make anything think this was meant to be linked to Resident Evil.  It couldn't even manage to be a good story in its own right either, a special agent on his first day on the job goes to Europe to fight a cult of monsters and rescue the presidents daughter...and there ends the depth of the story.  What is this crap?

RE5 by comparison has none of these issues, the story is linked with the rest of the series, rather deeply.  The characters are the same ones from older games and keep there personalities.  Inventory space is very limited compared to 4 and resembles the older games much more and the ammo amounts you can carry as well as what is dropped is also limited and much better balanced in proportion to the number of enemies you will be fighting.  If my issues with RE4 were because it isn't 'old school' then I wouldn't like RE5 either, but I do.  Alas, it is just a rather bad designed game that got a freebie promo because it was a new shooter style.

RE4 was for people who:

1. Never played a RE game before

2. Aren't very good at games

3. Do not care for story at all