The first article is almost pure invention, although it got one thing right, merely that early Irish kilts were solid colours.

However, they were mostly saffron or green, the former to represent dye often used in the Irish leine (tunic) and the latter to represent Irish nationalism, with which the colour green was associated since the rebellion of the United Irishmen in the late 18th century.

The other articles are mostly right where they stick to the bare facts, but completely out of wack where they express an opinion.

Irish kilts are over a century old. If that's not traditional/historic then I'm a Chinaman (which, BTW, is a type of throw, or a type of pitch if you're an American, in the game of cricket).

Moreover, the kilt is derived from the Irish cloak (brat), which was reportedly striped wool and most probably often tartan, as tartan remnants have been found that predate the influx of the Irish gaels into the highlands by thousands of years (I know that's already been posted). Yes, the picts were there first, but the kilt isn't derived from pictish clothing, and neither is pictish spoken there anymore.

So Irish kilts are old (enough for me) and Scots kilts are derived from Irish clothing, although not in the way the article says.