Your right, Al Qassam bombarbment of Israel should get mentioned. Then protesters would be more likely to mention that the ceasefire applies both way. But, you should not assume that because they do not mention it, they are opposed to it. Most protesters are fair-minded.

Al Qassam's violations of the pre-Oct7 ceasefire were regularly condemned.

(As for the news link: I note that the victim were soldiers. Tragic, yes; war crime, no. No doubt that there are numerous instances in which Israel noncombatants are killed and those should get internatioanl mention.)