A bubble is when the price of something is far higher than the fundamental value.

First of all, consider that we are talking about to the thing that is closest to a global scale free market that the world ever had. So the bubble concept will be biased towards it, since the market will regulate itself and the fundamental (or intrinsic) value of the asset won't be fix, as it will be linked to what the market think it should be priced.

Bitcoin gives you ownership of nothing (a stock gives you ownership of tangible assets)

It does gives you ownership of your share, again, the concept of digital asset is hard to be inserted directly into the current economic market.

Bitcoin pays no dividend
Bitcoin gives you no right to future payments (bonds give you the right to payments)
Bitcoin gives you no patents or trademarks

Indeed, it's only hold and trade.

Bitcoin gives you no legal rights

Again, it's a new concept, so there is no solid laws yet, but it's just a matter of time. Regardless, a crime is a crime so ordinary laws will still try to garantee your assets, as already happened.

Given these facts, you Bitcoin fans need to prove that the fundamental value is different from zero (or close to zero) - otherwise it is a by definition a bubble

Digital asset and free market. If you try to insert both directly inside our current economic ways you will have a big problem (and that's exactly what is happening). You will need to sit and wait to see if it's truly a hype-bubble or it hold true value.

Another thing is BTC can be valued at $1kk or $1, it won't change a lot, think about it deeply: it's overseas "currency", you can hold or sell so you can use it as a long term investment or day trade (not recommended due high fees and slow transactions, but altcoins will do) and you can buy daily stuff (each day more things are available).

Considering all of this, BTC can be considered at the same level as the current monetary system, but without government, it's like having a bunch of dollars stored in your bank, but in exchange of the regulation and relative safety you have the unregulated market with the value changing based on the free market will.