Simple. because they scared UEC students perform more academically well than Diploma/STPM Oren students compete masuk IPTA.

Later every Oren need to work much more harder because UEC student raised the bar.

But UEC is accepted in NTU/NUS / Taiwan / China, somemore most of them get scholarship.

Otherwise is just IPTA staff malas filter students.
Not like masuk UiTM. Syllabus in Uni, unless UKM all English.

Because we inherited UK Education System since we gained independence.
Even our government formed MPM/STPM, the original UK A-Level papers were "translated to Malay" in the initial years of MPM in 1970s.

Until our MOE / MOHE managed to stand with its own two feet, and create their own papers.

No one gonna favor STPM, if given a choice, unless you are "poor", or die die ego problem want join STPM, since the education revamp in 2013 to Modular System.

Alot of Malaysian Chinese, rather pay full or find "backdoor" programs to direct enter gov. unis.
Then these few years popped up many IPTA Foundation Program. RM 20k++ for one year scam.
Claimed you score well, maybe can "grant" a backdoor to IPTA... Then mana pula program to new, can't enroll via UPU.
Then still ended up paying unsubsidized tuition fees in Malaysia.

Otherwise, you go Private University's Foundation/Pre-U Program, majority all Malaysian Chinese faces.
Go to any A-Level College in Klang Valley, Johor, Penang, 90% of the people are Malaysian Chinese from SPM/IGCSE.

Nothing wrong, as long they can absorb the content and it resembles most country's High Schools learning outcomes...
Mainly for STEM subjects or Econs / Business Studies / Accounting.

FYI. UEC History is not CHINA focus.

SUEC History - https://uec.dongzong.my/exam-info/examinati...ior/19-shistory

Paper One: Multiple Choice Questions (25%)
Answering time: 40 minutes.
Malaysian History: 10 questions;
Southeast Asian History: 2 questions;
East Asian History: 6 questions;
World History: 7 questions.
Answer all 25 questions.

Paper Two: Structured Questions (75%)
Answering time: 2 hours 10 minutes.
Part A: Compulsory Questions (15%)
1 Malaysian History question is compulsory.
Part B: Essay Questions (60%)
Group A: Malaysian History, choose 1 out of 2 questions;
Group B: Southeast Asian History, choose 1 out of 2 questions;
Group C: East Asian History, choose 1 out of 2 questions;
Group D: World History, choose 1 out of 2 questions