Probably every single western mainstream media outlet, be it Radio, TV, Newspapers or Internet, has at least once used the phrase „Assad is bombing his own people“.

Interestingly, whenever the insurgents in Syria capture a town or village and the inhabitants flee towards government-held areas, immediately some „activists“ are quoted claiming that the people – who we are supposed to believe are entirely pro-rebels and against the Syrian government – do this in order to escape from the subsequent bombing by the Syrian army.
This „logic“ is difficult to comprehend because it basically implies the following:
1. Before their town´s capture the inhabitants did NOT flee towards the rebel-held „liberated“ areas
2. The people, especially the supposedly oppressed and marginalized Sunni majority choses to continue being „mistreated“ and suffering the evil of the „Assad regime“ instead of joining the rebel ranks to help „liberate“ further places in Syria
In addition the question should be raised in reverse whether those „activists“ would assume civilians fleeing toward rebel-areas are government supporters trying to avoid rebel shellings, tunnel and suicide bombs. (?)

Now, to connect the issue with IS, let´s take a look at the takeover of the Yarmouk camp by IS. It is said that from thr original 200.000 residents of the camp all but 10-20.000 have left. Further, it is said that IS controls 90% of the camp.
You can bet that if the Syrian army and allies shell and bomb the camp, our „activists“ will report of the regimes „indiscriminate“ shelling of civilians. All the while there are still pockets of resistance by „moderate“ heroic rebels who try to repel IS, of course without harming any civilians (except „Shabiha“ probably) and entirely hurting the radical IS militants, whom at least parts of the MSM are still portraying as a creation of Assad or in cahoots with him.

To summarize, we „learn“ that while…
– the Israelis act with maximum „restraint“ and exclusively target „terrorists“ and in the process „regrettably“ kill thousands of civilians
or
– the Saudis destruction of a neighbouring country´s entire military, industrial and civilian infrastructure is merely a tragic and unavoidable collateral damage of „defending“ against an allegedly Iranian-backed militia (which has been operating on it´s own country´s soil
…Assad and his majority Sunni army are deliberately and intentionally killing the „own people“, simply because the latter are Sunnis and demanded basic rights.
The actions of the Syrian army, we are supposed to believe, have nothing to do with militants (including IS) infiltrating neighborhoods and leading to the civilians subsequent departure.
And even if IS should take over the entire 100% of Yarmouk and only 1000 residents would remain you can be sure that „Assad“ does not bomb the camp to fight IS but to kill his „own people“.