The laptop is unlikely to be legitimate. Claims by conservative disinformation sites to the contrary - the NYT didn't 'admit' it was legitimate.
There really is no reason to think it is legitimate.
If the laptop has actual Hunter Biden emails on it - no one with any knowledge of espionage would be surprised. Only morons who know nothing about espionage would expect that it would be completely faked, or even mostly faked. The problem is that it takes an enormous forensic effort to determine what, if anything, on the laptop is legitimate. All of the innocuous and meaningless emails are probably legitimate. Any incriminating email, photo, video, or other document has to be treated with extreme caution.
Russian intelligence does forgeries frequently to frame political opposition,
https://www.forbes.com/sites/thomasbrewster/2017/05/26/russian-dnc-hackers-planted-leaks-with-fake-data/We know there was a forged identity and forged document used in the Hunter Biden story,
https://www.nbcnews.com/tech/security/how-fake-persona-laid-groundwork-hunter-biden-conspiracy-deluge-n1245387So anything found on the laptop that is supposedly incriminating has to be assumed tainted and a forgery until investigation can determine from other sources if it is legitimate.
It is entirely possible that some of the legitimate emails by Hunter involve illegal behavior. So the fact that some apparently incriminating emails are verified to be legitimate isn't surprising. This doesn't change the fact that the laptop was likely a Russian plant and likely contains some amount of forged documents.
Given that Hunter Biden was already being investigated by the DoJ under Obama, it isn't surprising that there were legitimate emails related to that investigation.