In today's digital economy, digital services are based on the general currency equivalents, such as contracts and so on. There is a clear temptation in some current initiatives to free themselves from this by using crypto-currencies and blockchain. However, while they are often presented as alternatives to the model of the major online platforms by their advocates, the models emerging from Web3, based on blockchain [[["Blockchain is a technology for storing and transmitting information that is transparent, secure, and operates without a central control body. It is a database that contains the history of all exchanges between its users since its creation. It is secure and distributed: it is shared by its various users, without intermediaries, so that everyone can check the chain’s validity. There are public blockchains, open to all, and private blockchains, where access and use are limited to a certain number of players. A public blockchain can therefore be likened to a public, anonymous, unforgeable accounting ledger. As the mathematician Jean-Paul Delahaye writes, we need to imagine 'a very large notebook, which everyone can read freely and without payment, on which everyone can write, but which is impossible to erase and indestructible’” CNIL, « Blockchain » : https://www.cnil.fr/fr/definition/blockchain#:~:text=La%20blockchain%20est%20une%20technologie,sans%20organe%20central%20de%20contr%C3%B4le]]], smart contracts [[[A smart contract is an intelligent computer protocol capable of automatically verifying and executing predefined operations or instructions (negotiation, execution, termination, etc.). They are based on blockchain technologies to guarantee their integrity and inviolability.]]] and NFTs [[[A digital token, fungible or not, is a unique digital asset (an avatar, the avatar's head or even an avatar's hair), which is issued and exchangeable on a blockchain network. Tokenisation works as a flexible legal mechanism through which people can define the digital and physical properties of programmed rights. Non-fungible digital tokens can be used for a variety of purposes: membership (closed communities can provide memberships in the form of NFTs to reflect the scarcity of seats in a closed club), loyalty (equivalent to accumulating points), ticketing (a ticket in the form of an NFT guarantees its uniqueness and authenticity), identification of digital or physical goods (NFTs can be attached to physical items to ensure their traceability and transparency), voting, etc.]]], raise a number of questions, as we have seen (see “Digital assets and tokens”).

Furthermore, under the pretext of a better distribution of digital assets' value due to each person being able to own all their data (objects created, behavioural data, etc.), an excessive commoditisation of human activities in the digital space could quickly emerge due to the absence of intermediaries, and therefore reduced or even zero transaction costs [[[For an understanding of the challenges, promises, and limits of Web3, as applied to social networks, see: Renaissance Numérique (2022), "Decentralised social networks: towards an ethical Web3?": https://www.renaissancenumerique.org/en/news/decentralised-social-networks-towards-an-ethical-web3/]]]. The risk of widespread commoditisation of our digitised social interactions should also be of concern to us, because of the possibility of monetising, and therefore promoting, immersion. This prospect is not without raising a number of questions relating to people's health (with regard to capturing their attention, screen time, etc.) and ethics.

We should also note that while interoperability is often considered from a technical point of view (interoperability of headsets, operating systems), from an avatar and user identity point of view, or from a digital asset point of view, it is rarely considered from an economic transactions and value point of view (or only to a limited extent, to address currency and transaction payment matters).

Consequently, will these immersive universes be able to generate a robust atmosphere of trust, capable of drawing in and consolidating exchanges and transactions, and establish themselves as the de facto standard? Would it be possible, and even advisable, to build standards in this field, given that current projects and experiments seem to diverge in terms of the digital environments they wish to offer?

Business opportunities, or at least the hopes that fuel them, seem to take precedence over the actual uses of metaverses (see “A damp squib?”). While there needs to be room for innovation and the emergence of a variety of different business models, it is also important to monitor their deployment in order to minimise any adverse effects on users. The governance of these metaverses needs to be considered in all its various dimensions.