People need to understand China first before making claims.
The 5 Million console is a just a limit being currently imposed by the Chinese government. This can be changed at any given moment. The reason for such a limit is for the Chinese government to have greater control over the market.
If 5 mil consoles sold in 1 week, before the limit would be improved China would bring some sort of extra rules/taxes to MS. Such as greater VAT % of game sales, more control over online features etc in order to twist MS to conforming to their rules.
If it takes years for the 5 million to sell, the limit might be increased with less restrictions and regulations on the consoles.
Basically, if the XBO is popular in Chine, the more control the Chinese will want over the device in their region.
I hope that XBO becomes successful in China. It's such a big, potential market and growing so fast each year. I would love to see how Chinese game devs would be able to create. With a much cheaper labour market they could potentially create massive games compared to Western/Japanese ones on the same budget.
However, with this labour market, I hope it wouldn't endanger jobs of companies who care about $$$.