Good point, at least when a split happens everyone gets their "free money", even tho nothing is really free, when a split happens it has consequences so it's not going to be totally free. But in the long term you end up with more BTC as you dump the fake BTC and it always ends up recovering.

But we can't have this circus going on frequently because it's just not serious.

I don't think we could equal these events

Though I like your analogy too. The main difference is that Bitcoin holders are not given original bitcoins (created out of thin air). If we cut the crap about Bitcoin Cash, people are basically given free dollars (by selling their Bitcoin cash tokens for fiat) with which they can buy more real bitcoins. If anything, it works in the opposite direction in respect to fiat quantitative easing. In this way, this giveaway should rather be called quantitative tightening since it increases demand for regular Bitcoin leading to its higher prices (and higher interest rates if we are to extend the analogy)

And that is my point too

That is, in the case of cryptocurrencies it actually works in reverse, so your (Bitcoin) savings don't lose any value (unlike traditional QE). And since most people will nevertheless spend these giveaways on buying more bitcoins (what we already witness, anyway), it would in fact work as a quantitative tightening, not easing. Even if you don't buy bitcoins but buy, say, litecoins instead, it would still work in the way I described, and the net effect would be essentially the same (but then with regard to Litecoin, obviously)

It is certainly not impossible

In fact, it is even somewhat easier. Bitcoin has reward halving through which the market supply of coins is diminished (that should obviously be construed as quantitative tightening). Conversely, the reverse process by which the market supply of coins is increased should be considered as quantitative easing, i.e. more coins entering the market within the same amount of time (let's call that reward doubling or tripling, or whatever). Though I don't know if that has ever been done in practice for any coin, but it is certainly possible to do. Aside from that, just raising or completely removing the cap for capped coins should essentially work in the same way