I just don't think we should call something a scam until it has actually scammed someone. I think pointing out reasons why you think it will fail or is a dangerous investment is fine so long as the information you are providing and/or basing these assumptions are correct.
I do agree that Bitconnect and other investments are High Risk and should only be considered by seasoned investors and/or investor who truly understand the risks.
Unfortunately there is a lot FOMO (fear of missing out) causing many to just "jump in without looking," and some may lose because of this. So warning others, especially newbie investors is again good.
As for Bitconnect, on thing to consider about its (supposed trading bot) is that is has only been active for about 1 year, and in that year Bitcoin's price has definitely increased by more than 1% per day, so in theory Bitconnect could just sit on the Bitcoin and have easily gained that 1% per day or more without Even Trading a single bitcoin. At this point, only upper management of Bitconnect truly knows where the money comes from, but don't forget that they do make money every time Bitcoin is trading on the Internal Bitconnect Exchange as well.
So yes, the fact is no proof of Bitconnect trading bot, but Fact also no proof that it Does NOT Exist either. And yes math could prove the impossibilty of that, but then again, tell that to Bitcoin that has done so in the last year alone, go up more than 1% a day, impossible but yet it happened.

And from what I understand, rumor has it that the referral system might be removed or rather discontinued.

And after they distributed Bitcoin cash, they had some issues with Bitcoin withdrawals, where some users took out more bitcoin that Did Not Belong to them. They shut down the system for a few days to audit and fix the mistakes.
Everyone Screamed SCAM, yet they fixed the problem and came back.

Herbalife Corp was called a scam and is still considered by some to be a scam, yet their Company Stock still trades perferctly on the stock exchanges. They have made changes to their business model as needed. Bitconnect can and has done the same in order to stay viable. So is the future risky for Bitconnect? Yes.
Can Bitconnect change its business model to continue being successful? Yes.
Is Bitconnect a scam? Maybe, Maybe Not.
Will I lose money if I don't invest in Bitconnect? No
Will I make money if I don't invest in Bitconnect? No
Will I lose money if I invest in Bitconnect? Maybe
Will I make money if I invest in Bitconnect? Maybe

NO vs. Maybe

I will take the Maybe any day because I guarantee that if I take the NO, I go sideways (make nothing) or nowhere (stay the same).
I guess that is why people play the Lottery, for the Maybe.