We have 300+ posts on this on two other threads. Do we really need more of this crap?
I'm going to play devil's advocate here and I'm replying to your post because, across the recent 737 Max threads you at least appear to be the most vocal of those criticising any suggestion of a total Max 8 grounding.
On this forum we (mere mortals) are constantly reminded that the aviation industry is fully ingrained with a safety first attitude. People in the industry are highly trained and certified to a level seen in very few other industries. Just a few months ago we had a discussion where a highly respected pilot from a highly respected carrier suggested that a flight might not depart because of missing duvets as it was a very real safety of flight issue. Again it was made clear that "we do not take risks - period". To be fully open about raising this topic, I apologised profusely to said member because my tone during my replies in that conversation was not up to standard.
Now we have 2 almost brand new 737 Max 8 aircraft lost during initial climb. Some are suggesting that these 2 accidents absolutely did not occur during the same phase of flight because MCAS is not active with any flap extended. Other data suggests that the aircraft was a ~400kts, well above max flap 1 speed and several minutes after departure at which point flaps would usually be fully retracted. In other words, it is not yet fully clear whether flaps were extended or not, nor whether MCAS would be in play or not.
You have made the point that not knowing the cause of this latest crash is absolutely not a reason for a grounding, that it is a crazy idea and anyone even suggesting such is basically a dumbass. Heck, we even had a moderator stating that ANY suggestion of a grounding would result in the post being deleted.
Now we have CAAC grounding the type under their control, with others already or likely following. So there are those in the industry (and in a position to make such a decision) who have decided that a grounding is the right thing to do, which would suggest that those calling any such action crazy, and moderators suggesting that posts would be deleted are probably over-reacting more than those they are pointing the finger at for over-reacting.
CAAC is probably the LEAST likely authority to make a decision based on what is written on A.Net, so let's not go there. Others have already stated that CAAC's decision was only made to protect their Airbus final assembly business, which personally I think is a disgusting thing to suggest without direct proof.
Anyway, back to my main point:
1.) We have two Max 8 total loss accidents within a short time period.
2.) Both were during climb out.
3.) We "know" that one was directly related to MCAS.
4.) MCAS has not been categorically ruled out on the second.
5.) Boeing have a "procedure" in place (which they didn't widely publish before entry into service) for what to do when your new plane is trying to kill you.
6.) No absolute fix for potential MCAS flaws has been released (a procedure on what to do to arrest massive nose down pitch during a phase of flight where altitude is not on your side is not a fix!)
..and you state that not knowing a reason for a crash is absolutely no reason for grounding a fleet. What if there was another crash next week and we still don't know the reason? What if there were 2 more next week (and one was an American carrier) and we still don't know the reason? At what point would it be OK to take preventative action when you still don't know the cause?
I've been an aviation enthusiast for 40+ years and I am becoming more confused every day. On this forum we hear the same reasons being given to justify both action and inaction but you can't have it both ways.
The very fact that CAAC has decided to ground a fleet, in my humble opinion, would suggest that those who were criticising even the slightest suggestion of a grounding might want to rethink their position.... or maybe offer an apology.