Firstly the M50 is ~390 grams compared with say the 950 grams of the 5DsR so there is a big difference in the lenses also ... for example the lens attached in this shot is 130 grams and my general lens I use for both the 5DsR and 5D Mk III, the Canon EF 24-70mm f/4L IS USM Lens, is 600 grams. So, in effect, the setup with the M50 is 520 grams compared to the 1.5 kilograms of the DSLR setup.
(Note that the premium APSC, the 7D Mark II is actually 1.3Kg body only)
Secondly the Canon mirrorless have access to the whole EF/EF-S lens range and operationally the latest models are as good as most of the APSC DSLRs excepting physical things such as buffer sizes but it does have a tilt-swivel touch-screen, focus peaking, wi-fi, bluetooth, nfc and 4K video.
It is really unobtrusive to carry around and almost as fast as a premium DSLR.