Bitcoin and ethereum are not two competitors that are fighting over dominance but two separate networks that have two very different goals. In fact the success of both networks will actually help the other as it goes cryptocurrency a more robust eco-system that can house dapps as well as a gold-like asset. One helps the other and brings in users and investors into a new class of assets that has already become mainstream with a lot of room to grow.
Bitcoin The Asset
Bitcoin is the face of crypto. Like it or not it is what is driving the market and what you look to to see how the market as a whole is doing. It is on the success of bitcoin that the market is hinged on and it does not look like this is going to change anytime soon. Although there are a lot of other coins and networks that are popping up (and some doing very well) bitcoin is the "gold" of the network that anchors the ecosystem. Outside of stable coins it is the safest option for crypto and it is the one that investors and countries are stocking up on. BItcoin is decentralised with a limited supply. It is established as the digital gold of the market. It is possible that dapps could be built on the bitcoin network but that doesn't need to happen for bitcoin to be successful. Bitcoin also does not need to be money, although ti can be used as it. Bitcoin is already doing what it needs to do and that is be a "hard" asset that gives weight to the crypto world.
Ethereum The Network
Ethereum on the other hand is a network where dapps are being built on. This is where developers are designing different programs to use where millions (maybe billions one day) of users can interact with the chain. Ethereum success is dependent on the network and the dapps on top of it. Fees have become a major concern right now but side chains are making ethereum a powerhouse. The ethereum network needs a lot of users and developers but it doesn't need to be treated like gold. This is where bitcoin comes in. Value is already in the network and stored there with the gold-like asset of bitcoin.
The two assets together held store value in this new world while allowing a network to build of users on dapps. The two are working together to bring in investors and users around the globe. People are into crypto for different reasons and it will be the best for the ecosystem if there are as many uses as possible to attract as many users that you can. There will be people who will want to hold and others who will want to day trade. While there will be others who are happy getting their divs from defi.
There are other chains right now that are competing with ethereum and networks like solana and avalanche are really making headwinds out of nowhere. Pretty crazy to see their increase in such a short time. But ethereum right now is on the top and with updates to the network still happening the battle is a long way to go. And there is room for more than one network.
Bitcoin looks like it will hold as the gold of the ecosystem and other coins will work as the network of the ecosystem. The success of one asset does not discount the success of another. The future is bright for the world of cryptocurrency and there is a lot of space for different coins and networks to thrive.