It is rather difficult to decide which is better between Ripple (XRP) and Ethereum (ETH).
The first thing to note is that these are two very different cryptocurrencies and platforms.
The differences are such that it becomes difficult to make a comparison, because the two platforms have been designed for different purposes, and as a result, the two cryptocurrencies behave differently.
Firstly, however, a distinction must be made between the platform and the cryptocurrency.
In the case of Ethereum, the cryptocurrency is Ether (ETH), while Ethereum is the actual platform, that is, a decentralised network able to, for example, execute smart contracts.
In the case of Ripple, the cryptocurrency is XRP, while the platform, RippleNet, is comprised of various systems and services, including xCurrent and xRapid.
Ethereum is a decentralised project created specifically to enable the execution of smart contracts, which remains one of its greatest strong points to date. For instance, the so-called decentralised finance (DeFi) is mainly based on this infrastructure, and the fact that it is completely decentralised is a fundamental characteristic of it.
Ripple, on the other hand, was created as a centralised payment system to make transactions faster and cheaper. Over time, the blockchain has opened up, and XRP is now considered less centralised than it was in the early days. However, the role of the private company Ripple is still very relevant, to the point that there are also some ongoing cases concerning precisely the overwhelming role of the company within the ecosystem.
It is no accident that Ripple is working a lot with traditional banks and financial institutions, while for the decentralised approach to finance, completely independent from banks or institutions, the Ethereum platform has been chosen.
As a result, the differences between the two projects are many more than the things in common. The commonalities could be summed up in terms of market capitalisation of the two native tokens, in second and third place after Bitcoin, in the fact that they have existed for several years now, in the way they rely on blockchain and encryption, and in the support offered for smart contracts, even though they are not native on XRP.
In light of this, it is impossible to say which of the two projects is better. At most, it would be possible to analyse and compare the performance in each individual use case, although for some it would be better to use Ethereum, while for others it would be better to use Ripple.
The main differences are clearly that Ethereum is decentralised and uses proof-of-work, which makes ETH mineable, while XRP cannot be defined as truly decentralised, and it is not mineable.
Moreover, the fact that Ripple still holds a huge amount of XRP, some of which are occasionally released on the market, makes the evolution of the price of XRP less performing than that of ETH: for example, since early 2019, ETH has gone from about $130 to about $180, while XRP has fallen from about $0.35 to $0.3.
As such, Ripple and Ethereum, or XRP and ETH, are not alternative platforms or cryptocurrencies between themselves, to the extent that in reality, they do not even compete with each other. And they are not even alternatives to Bitcoin, which is yet another thing.