The evidence I've been accumulating seems to suggest the following timeline:

1930s - last gasp of the old turn-of-the-century cloisonne workshops, given the coup d'grace by the Japanese occupation of 1937

1950s - the CCP subsidizes and supports the cloisonne craft, consolidating 40-something tottering workshops into the Beijing Enamel Company and the Beijing Art & Crafts Cooperative. Dedicated art students and older artisans coordinate to resuscitate the cloisonne industry, creating some extraordinary works in the process

1960s - early 1970s - The Cultural Revolution throws a monkey wrench into the whole cloisonne renaissance, with artists forced to produce works appealing to "the workers," whatever the hell that was supposed to be.
As any artist can tell you, stuff that appeals to the lower less-educated classes is 1) colorful 2) stereotypical. It has to be bright and reinforce common sentiments. Pretty, but totally corn-dog.

1970s-early 1990s - re-opening of trade with China after an embargo of 20 years creates a flood of cloisonne, as the Beijing Enamel Factory ramps up production to fill foreign orders, employing up to 2,000 workers and offering pensions to retirees. Chinese arts and crafts workshops encouraged by the government in order to generate the foreign exchange needed for technological information and infrastructure development.

1990s - Deng Xiaoping's economic reforms beginning in 1978 lead to China's dominant position in the world economy for consumer production and export; but, alas, leaves the traditional crafts such as cloisonne manufacture in the dust. Why work for a mere 22 Yuan a day in a cloisonne factory at a craft that takes about a decade to master when even the worst-paid person in a ShenZen hellhole of a sweatshop is pulling in 100 Yuan?

2000s to present - Beijing Enamel Company re-organizes after bankruptcy. Huge barriers to profitability, but soldiers onward both with beautiful new designs and repros of classic Ming pieces (that are promptly pirated and reproduced by knock-off workshops) with a reduced workforce, mostly female, of about 300.
See the video referenced at the start of this thread.

So, if consumers see no cachet in beads that are no longer cost-effective to produce, why make any more?