Vw beetle warning light

There is no reason for rejection for traction control

What does the mot inspection say regards traction control

Has it got ESP?

Does it have a separate warning lamp for ESP faults?

The one I had in today did not have ESP

It did have ASR (or traction control)with on/off switch
ASR is VW anti skid reduction not ESP, meaning not all vw beetles or other models in the vw range will have ESP fitted just traction control.
Traction control is not another acronym as people might think for ESP ,where the manual states "other acronym "
refers to trade names that volvo,Porsche and Honda etc etc use.

It may well be that ASR system is fitted to some early vw but no ESP system ,but all vehicles that do have ESP will have ASR as a sub system inter grated with the ESP .
If the model beetle mentioned in the original post does have ESP on/off switch and the malfunction triangle is illuminated on its own,the chances are its the traction control that's at fault,so failure is NOT justified.

We test the full ESP system not just part of it (ASR/traction control.) therefore it would have to be beyond doubt for a tester to ensure the ESP is defective .this is where the reliable data is very important,if its not available then pass and advise.the owners booklet is 1st place to try.
Always try (where needed)to refer to the manual before making a decision

If its the ESP that's defective a good give away is the ABS malfunction lamp will normally illuminate along side the ESP lamp.

Well, I would have to say nitros44's advice seemed pretty clear, but of course the final decision always rests with the tester carrying out the test.