In my opinion, you are commenting here on many points where there is no major dispute. That is, if we compare A. receiving dividends and spending them on something other than the same stock and B. the shareholder not selling during share buybacks, we are talking about two completely different things, and in my opinion, there is little point in comparing them, nor do I think there has been much debate about this. In the former, the stock weight in this stock does not change; in the latter, it increases, meaning the portfolio allocation changes. And you are completely right that if the weight of a certain stock is quite different for two investors, only the future will show who fared better.
The previous heated discussion was related to which method of profit distribution is better IF the same stock weight is maintained in both cases. That is, either the profit distribution is cashed out, or it is not cashed out but the stock weight is increased, and this is compared with two different profit distribution methods. Then a very clear comparison can be made as to which one burns more in taxes under certain boundary conditions. In this, for example, the company’s future development does not matter. Only the method of profit distribution. (And costs and whether one can sell fractional shares and whether one uses a book-entry account (AOT)).
In my opinion, the biggest problem is that a surprisingly large number of people do not understand and do not know how to calculate that difference in taxation - even after seeing how it is calculated. Instead, they imagine that because 25.5% < 30%, dividends would be cheaper. Or they imagine that dividends are extra money appearing out of thin air. Which is not true for reasons that have been gone through N times with calculations. In my view, this misunderstanding is a quite significant problem, and I will certainly address it whenever I happen to read such a comment. That shouldn’t be taken as a personal insult either 
And absolutely everyone is allowed to do what they want and invest in whatever they please, as has been stated many times. If someone likes dividends, then just put dividend stocks in the portfolio! This discussion is only about as many people as possible making an informed choice based on facts.
I must clarify, however, that this is a misleading comment. On a conceptual level, an investor ensures money in their pocket in exactly the same way with share buybacks when they sell an amount equal to the profit distribution every year. It is then a matter of taste whether a few clicks are too much trouble or not, and there is no single right answer to that.