Meh. The media screaming "concede" is just them being bitter they didn't get a more decisive win. Plus I suspect them being a bit crazy and drinking their own kool aid. They've been throwing out rhetoric for years to portray Trump as literally Hitler, and I suspect many of them privately think that and manage to work themselves up in a bit of a tizzy over dumb shit like Trump answering 'We'll see' to a question asking him to commit to "a peaceful transferal of power after the election". Which as an aside is a rather dumb question as Trump has no real options but a peaceful transfer of power unless you count whining and suing as violence and of course Trump wouldn't commit to not doing those. The question should have been if he'd commit to a quick and orderly transfer of power. Anyways, there's also probably a dash of "make him bend the knee" to it. I suspect in the media's mind, they've called the election so Trump should bend the knee to them and concede. If he waits until the electoral college votes - or even until the electoral votes are formally counted - he's not bending the knee to the media he's bowing to the electoral college. So they're screaming 'concede' in basically a temper tantrum that Trump won't do what they want him to do.
In fairness to the media there are some valid practical aspects that may be of genuine concern. The whole reason we amended the constitution to move inauguration from March to January was so that an incoming president could get on the job quicker in times of trouble, rather than have an outgoing president sitting around for months getting nothing accomplished. To go with that, we've also developed a lot of processes and procedures to get a newly elected president fully up to speed and ready to go as soon as he's inaugurated. Trump's currently gumming up those processes by refusing to concede and holding to a forlorn hope that he can find a way to remain in power. That's probably pissing off more than a few people as well, especially as he's not being particularly graceful in the way he pursues said forlorn hope.
In any case, a sign that there's fraud going on is probably the last thing I'd take the media complaints to indicate.