Is it possible? I wanna explore everything, but I still want to see how the story ends.

No. But you will be informed when it's the point of no return, so make a save and come back after you're done.

If you are on the PC there is already a mod for this.

Yea I'm on PC. I didn't see a mod at the Nexus, where is this one?

Nope. Finish all your exploring before doing the last quest.

I can't find it right now but I swear it was on the NV Nexus a couple of hours ago. The modder must have removed the file for some reason.

You would think that Bethesda learned their lesson after ending the game with Fallout 3. They said it was a mistake, which is why Broken Steel corrected that mistake & let you free roam & complete other tasks after beating the main storyline. But here we go once again!

I guess we can expect another "Broken Steel" type of DLC that will let us continue to play after the main story is completed. Nice job, Obsidian.

could be for sales purposes, make you buy dlc in order to keep playing your game after beating it

bethesda didn't make this game obsidian did so if you want to blame someone blame them, and it was said that after you finish the main quest it doesn't make sense to go on

Or it's because the game ends with something drastically changing like blowing up the hoover dam or nuking vegas, which would require a complete content overhaul.

Which, according to some of the Dev interviews I watched, seems to be the case.

Considering "Broken Steel" was the best selling of all the DLCs it's no surprise New Vegas has an ending.