Ah, the old Keynesian argument...

Um yes? And reality consistently confirms Keynsian/demand-side modeling.

Keynsian demand-driven economy is the root of all evil, i.e. market bubbles that pop eventually. Everyone except market speculators would be much better of with supply-driven economy and small deflation.

For one it would provide incentive to save money and spend it wisely, instead of mindlessly buying all that unnecessary crap.

> Everyone except market speculators

And debtors. The very notion of taking out a loan for something becomes nigh impossible with a deflationary currency, particularly one as deflationary as Bitcoin. Seeing as how the lower and middle class tend to take out loans for all sorts of reasons (since if they had the sort of cash lying around to buy homes and cars and appliances and such outright, they probably would be neither lower nor middle class), the direct harm such a currency would have is readily apparent.

While I'm skeptical of homeownership and car ownership in particular for other reasons, absolutely a healthy capitalist economy needs easy access to credit for potentially socially useful activities.

Strange reading of Keynes. I never read him advocate for rampant wasteful consumerism. In fact many of his arguments about government intervention (investment) are derived by his observation that consumption is prone to drying up.

I also don't see how Keynes and speculative frenzies are connected, considering they existed long before his Treatise or General Theory.

Keynes advocated for rate cuts as a remedy for crises. His reasoning being that cheap credit will stimulate demand for consumer goods. It's almost the textbook definition of "wasteful consumerism".

Indeed, and bubbles are in assets not goods to consumption, and stimulus is supposed to boost consumption in the first order, so the comparison seems even more far fetched.

> ... his observation that consumption is prone to drying up.

Now that wording has a certain ring to it (in my ears).

"Consumption prone to drying up"? As if consumption alone were of any value. As if consumption were the foundation of all well being. As if it were something that needs to be tended to like some garden with flower beds.

Sounds more like ideology to me instead of reasoning.

Keynesian isn't a value judgement on whether various sorts of consumption are good. It's firstly a description of how capitalist economies actually work, and secondarily a toolkit of policy based on that description. The focus on demand is primary because how it affects the economy writ large.

In fact, Keynes himself famously thought that would be working 15 hours a week by now instead of...well...wherever all the work is going, some of which I suppose is propping up the consumption you don't approve of.

It's a pity then that supply side economy doesn't work.

Ah another free market neoliberalist. You do know that government intervention during Keynesian’s time was incredibly helpful for the macro economy - providing jobs and investment into long running avenues. Neoliberalism purports that the private sector will invest diligently but really we’re seeing companies use shortermism as a technique to just make profit.

And Keynes has empirically done very well, thank you.

Well, now that it exists, what would you as an individual rather keep your cash in compared to inflationary fiat held in an account with negative interest rate?

Genuine investments in companies, real estate, and other hard assets which actually produce cash flow rather than BTC whose value depends on the madness of crowds and the tweets of eccentric billionaires.

Investment portfolios exist. They also reduce the cost of loans, thus making it easier for companies to grow and speeding up innovation. In comparison, the only thing "investing" in cryptocurrency does, is encourage larger economies of scale for cryptocurrency (which, side note, has built in mechanisms to actively prevent it from becoming more efficient).

I don't know a single person who holds their money in 'cash'. They invest it in the market, real-estate, business development, etc.

I am one who holds cash. Not all, but not an insignificant portion either. I have a mixture of assets. Why not invest that cash? None of the investment opportunities that I see fit my risk profile. Example: I'm holding my stocks now, but I do not plan to buy more.

The average middle class (and below) person in any highly developed country has a mixture of assets, dominated by their house and cash savings in a bank. Most don't directly own financial assets -- stocks, bonds, etc. However, they are invested in a pension (national or private) that will certainly invest in financial assets.