What "use case" do you think bitcoin solves out of interest ? (Apart from making coin-grabbing early adopters rich)
so you really don´t know it yet? you been in this forum since sub $100 prices. you did not understand it back then, that is why you are no early investor. nothing to be ashamed of. but after 6 years and 6000 posts... i see...
how about:
permissionless, trustless, uncensorable, borderless secure and safe transfer of value.
unconfiscateable, immutable, truly decentralized and safe store of value.
Those are features of a blockchain, not monetary-economic roles.
Bitcoin is a reserve asset (relatively speaking in the blockchain space). As such its job is to collect and provide continuity to long term capital that's not deployed in some kind of active economic role. In any monetary system you always have a layered structure of diverse assets -
always. Thats because there are so many distinct priorities that may be in conflict for a given requirement.
For example, say you're a saver. You want to maximise return on your savings and don't care how they are denominated. You may or may not need regular "income" from your capital, or just protection against goods price inflation long term. That would be one set of priorities which may be met by - whatever: sovereign bonds, equities, indexed funds, gold, silver, bitcoin.
On the other hand, say you're a car manufacturer. You have a 6 month budgeting cycle during which the price of labour, raw materials and plant can go all over the place. On top of that you're exposed to potentially unfavourable currency volatility in foreign markets. Here, you're not interested in maximising return on capital, but rather running your production costs on budget and preserving the margin on future sales. So you invest in a completely different type of money - one that preserves your planning priorities and hedges your risks.
Contrary to the tunnel visioned mono-culture you've been promoting in this discussion, the crypto economy is no different. There will be and IS already a demand for a diversity of trustless monetary blockchains that address specific priorities ranging from realtime trading performance, through various hedging protocols such as stablecoins or commodity pegs, the whole smartcontract sector and crypto-derivative platforms, trustless auction exchanges, invoice factoring platforms, bitcoin clones that prioritise alternative aspects of the protocol, trustless hedging protocols for merchants such as Bitshares.
Bitcoin cannot do all this and was never designed or intended to. If you think one blockchain can run a whole crypto economy you're deluded. Also you can forget any "side chain" or "piggy back" nonsense as well because if there's one thing that's been learned from the old gold standard or trans-national currencies like the Euro, it's that single currencies are a disaster for diverse economies. They transmit all the rot from where the problem is to where it isn't. (Though that doesn't mean that we can't have world reserve asset bases like bitcoin but they are horizontal, not vertical).
The way that all these "alternative classes" create growth in bitcoin is that the monetary systems are layered on top of each other so that the utility assets are near the top and reserve assets at the bottom. One way that this is often expressed is in a metaphor known as "Exter's Pyramid". What happens is that most of the utility capital is deployed and recycled in the utility layers (such as short term business deposit accounts in the classic economy for cash flow). But some of these activities make "excess money" - i.e. profits - which have to be "parked" somewhere as they are excess to requirements. That's how capital starts to drift down through the pyramid and into the successive reserve layers below, adding long term value to them.
So be careful what you wish for. If you really want your BTC to grow, in my opinion you'd better hope the whole economy grows around crypto and that ain't gonna happen with one blockchain - albeit a reserve asset one. Trees have leaves for a reason, the bark on the trunk isn't too great at collecting light for photosynthesis since it's busy doing another job protecting it from reindeer sharpening their antlers. Similarly, altcoins will be the "collectors" of revenue and ultimately capital from a myriad of business sectors that bitcoin would simply never have found its way into on its own. Why do you think the Lightning Network is needed for example ? Because bitcoin can't even adequately fulfill the most basic of trading performance priorities and there are plenty more where that one came from.
What you want for bitcoin growth is LOW relative market dominance, not high dominance. That's also why you see jumps in bitcoin value taking place after a period of decline in dominance - because the high "capital collector" altcoin layers of crypto's "Exter's pyramid" have become saturated, get squeezed, and the excess capital moves to reserve storage in bitcoin.
Finally, I'm not the only one to have made this appraisal of the future structure of the crypto eco-system. Others have taken it much further, such as Tom Luongo who actually posted a version of the pyramid adapted to crypto. This is from a couple of years ago.