This phenomenon, however, has shown more demerits than its merits, as far as I am concerned.
Change the order;
As far as I am concerned, I believe that this trend has more demerits than merits.It is undeniable that the popularity of changing jobs and living places has contributed to the whole society greatly in various aspects.
... This line does not convey a clear idea.... You better re-phrase it
... I don't see these two reasons really matter for what prompt suggests you.
Why do people change jobs? or why do they change the place they live? I think this is mainly because of their career progress, career demands, education of children, facilities, etc.