Your linked article is about transcendental meditation - not mindfulness mediation. Mindfulness meditation research is well validated now – I can provide many meta analyses. You may also like to see the following recent articles:

https://www.telegraph.co.uk/health-fitness/lifestyle-changes...

https://theconversation.com/mindfulness-meditation-ten-minut...

https://www.psychiatrictimes.com/cultural-psychiatry/be-here...

https://theconversation.com/mindfulness-can-help-phd-student...

https://thriveglobal.com/stories/meditation-3-reasons-why-yo...

https://www.psychologytoday.com/ca/blog/being-while-doing/20...

https://www.psychologytoday.com/ca/blog/mindfulness-in-frant...