Given the massive increase in China’s economy over the last 30 years, this was inevitable.
Which, in part, is why Taiwan (& Europe) have a hard time "struggling to recruit enough soldiers and sailors" and field a formidable army/navy for themselves.
Relying on the American military & taxpayer can afford you to do many other things (i.e. socialism).
How was it ever one of Asia’s most formidable with only 4 subs?
Taiwan really needs to think out of the box for its defense needs. However, doing so can be very cost effective.
They will never win in a quality vs. quantity fight. So what they need is a vast number of cheap and effective weapons. For example:
Millions of free floating, “coffee can” naval mines. The ocean currents in the Taiwan Strait are well known. So if the mainland tries to launch a huge flotilla of commercial and warships, there can be a dump of tens or hundreds of thousands of these mines that could severely cripple the flotilla. They probably wouldn’t do much against a warship, but a large commercial ship used as a troop transport could be scuttled.
And if they hadn’t exploded after a given time, they would go inert and sink harmlessly.
Another idea is an “air armada” of “beer can” drones with 1000 pound bombs. Unlike the WW2 Buzz Bombs, they would have a simple off the shelf computer guidance system that would continually update a ‘hard’ guidance system that couldn’t be electronically fried. So if their computer was knocked out, they would continue with their last verified instruction.
A body with a bomb, an engine, and a fuel tank. With a cost under $100,000 per unit, they could crank out thousands of them. They could be launched from a tramp steamer, nowhere near the fight, to hit other mainland cities, even Beijing.
They could get at least 200 of these drones for the price of a single F-16.