This isn't even a good idea for partisan reasons. If a Democrat wins NE-2 on the presidential level, they're probably already winning the election. It's not like it'll make the difference between 269 and 270. Leaving it the way it is just encourages Democrats to spend money there instead of somewhere else which is both 1) Good for the Omaha economy and 2) probably marginally helping Republicans in swing states where Democrats would then have fewer resources.
None of this is true. Very close elections can and do happen. The President won NE-02 by 2.2 points. This is not a safe margin for future Republican presidential candidates.