> I would certainly put it ahead of many of the more marginal currencies in the world.

I wouldn't disagree, but nobody seems to seriously address the 51% vulnerability or the 100% likelihood of depreciation, which I think are the worst attributes.

It's circular logic to say BTC has to increase with halvings, and if that fails, mining consolidation would likely increase as it became transaction fee driven. Consolidation increases the risk of history rewrites in the 51% attack scenarios.

Further, the 2nd law of thermodynamics is inexorable. There will only be 21M BTC and even with the most elaborate data protections some number will be irretrievably lost in a random manner (or irretrievable up to the limit of the strength of elliptic curve cryptography, but then you hit far worse problems). Depreciation won't favor it as a currency, and it can't exist soley as an asset class. I know some some people will point to layer 2 projects but I haven't been convinced.

My conclusion is BTC is just not viable. Marginal currencies can be bad and bitcoin can bad, and having no good options is entirely possible, and sadly seems more common than not.

I have been substantially wrong about this up until now, though. I did my first dive into the technology when evaluating an employment opportunity in a blockchain related company around 2018, when it was $5,000 USD area. I've had the opportunity to buy large quantities and did not. So take it with a large grain of salt.