Congratulations on giving absolutely no argument to back up your stance. :rolleyes:
Seriously, apples and oranges is a cop out for the indecisive. You CAN compare apples and oranges, and you CAN compare Fallout 1/2 and 3 as well as you can compare say, Halo and Halo 2.
It has only been considered a cop out for the indecisive because most people are either unable to use it correctly or refuse to use it correctly. Of course they can be compared, but it would be pointless to compare them to see which makes the better apple pie.
FO1&2 vs FO3 threads are nothing but flamebait, but I'm gonna take a shot at it. Most of the arguments that people have against FO3 are more often than not the ravings of pure fanboyism. Often they'll say that the game doesn't belong in the canon because it deviates too greatly from the original story, that the SPECIAL system is too weak, that it didn't have the same quality of writing... blah blah blah. The fact of the matter is that most modern games seem to be being made as a replacement for cinema and literature. In fact, the video game market is roughly double the size of the box office. As a result, more and more gamers who in another life would've been movie snobs are being absorbed into the video game realm where developers are feverishly trying to satiate their lust for "good writing" with $60 cutscene collections like MGS4 and GTA4. It's not good enough that a game simply be fun, like FO2 & 3, or particularly well written like FO1, but today it seems that if they aren't both the game must be a failure.
As for the arguments about deviation from the original formula: bullocks. Metroid Prime was a complete deviation and still incredibly fun. Mario RPG was nothing like any of the little plumber's other incarnations and may have been the best in the entire franchise. Though the naysayers will never admit it there are a lot of rose-tinted bouts of nostalgia in their criticisms, but I can't say I don't completely understand. FO1 & 2 were only RPGs I played for my entire freshman year of college, and the only video games outside of what my SNES. To say I loved the games would be a gross understatement, but that is not to say that the games were without their flaws. One main reasons that FO1&2 was the only RPG I played for that entire year was because compared to most other RPGs of the time they were really easy. Incedibly easy. At times, even embarassingly easy. The worst thing about their being so easy is that I am terrible, TERRIBLE at mid 90s RPGs. I never got past level 5 or so on Diablo, Sacred, Baldur's Gate, any of the D&D Franchise... I was and am still awful at computer RPGs.
So what was the magic formula? SPECIAL. More like SPECIAL education, amirite? If you can count to ten, you can conquer any game that employs it. Realistically speaking, SPECIAL is only slightly more technical than the Blood Point system in White Wolf games... which required a measley ability to count to five. But even though SPECIAL games are easy, they are still FANTASTIC games because they are generally fun and quick but are still closely related enough to legacy RPGs to hold their own in the P&P arena... Except Lionheart. [censored] Lionheart.
I suppose my point here is that ever since Half-Life came out, gamers have this notion that they are owed some sort of mind-blowing cinematic experience everytime they pick up their controller. FO1&2, no matter how great they were, were not mind-blowingly cinematic. They were games written to fellate our ids and tickle our egos and at the end of the day be nothing more than light RPGs that are more fun than any of their more serious competitors. FO3, even though it has a million technical differences from the other two, serves the same purpose. It's one of those games, like its prequels, that mockingly echoes our mothers' shrill demand: "Don't get so mad... it's just a [censored] video game."
tl;dr
Of course these games can be compared, but you might be a little surprised to find more similarities than differences.