The ROCAF has always had a troubled history with their Mirages, not on just operational readiness, but the fact that they've often had shortages of spare parts.
Taiwan's Aerospace Industrial Development Corporation (AIDC) is studying the development of a successor...
www.flightglobal.com
"Upgraded and new fighters are essential for Taiwan's air force, with its Northrop F-5s in need of replacement and around half of its Dassault Mirage 2000s grounded due to a lack of spare parts."
Also, Taiwan's Mirage fleet was only upgraded to the latest standard in 2018. For comparison, the UAE's fleet of Mirages were all fully upgraded in 2003. Pretty sure a country with an economy like Taiwan wouldn't have problems upgrading their fleet even with the corruption that takes place.
Bringing Taiwan to the World and the World to Taiwan
www.taipeitimes.com
It's gotten so bad, that their MinDef is considering scrapping their fleet and going for a full F-16V fleet.
Keeping in mind that China was never happy with Dassault selling the Mirages in the first place.
www.nytimes.com
Point is, don't think the French won't sideline us just to appease the Chinese. Yes, the ROCAF do overuse their Mirages due to their strict operational requirements, but a country like Taiwan shouldn't have any problems buying large stocks of spares with their economy, unless someone is deliberately lobbying against it.
They're going to sell us the Rafale now to make a buck, but think twice if you think that they would help support our fleet in the case of a political incident with the PRC.