It’s an inescapable fact that a crypto project must be financially sustainable, and in 2020 this means millions or even tens of millions of dollars of funding. Some of this can be covered by common public-good-funding entities such as Gitcoin Grants or the Ethereum Foundation, but the scale of these mechanisms is just not sufficient to cover this level of funding. However, layer 2 projects launching their own token is sufficient - provided, of course, that the token is backed by genuine economic value (ie. prediction of future fees captured by the L2).
An important secondary benefit of a rollup-centric roadmap is that it leaves open space for L2 protocols, and these L2 protocols have the ability to collect fees/MEV 116 that can fund development, either directly or indirectly (by backing a token that funds development). The Ethereum base layer has an important need to be credibly neutral, making in-protocol public goods funding difficult (imagine ACD calls trying to agree on who deserves how much money), but L2s having their own public goods funding mechanisms (and/or contributing to Gitcoin Grants) is much less contentious. Leaving open this space can thus be a good strategic move for the long-term economic sustainability of Ethereum as a whole.
|Everyone moves to rollups||~3,000 TPS|
|Phase 1 (sharded chains) and rollups move to eth2 sharded chains for data storage||~100,000 TPS|
|Phase 2 (sharded chains with native computations)||~1000-5000 TPS (on base layer)|
It seems very plausible to me that when phase 2 finally comes, essentially no one will care about it. Everyone will have already adapted to a rollup-centric world whether we like it or not, and by that point it will be easier to continue down that path than to try to bring everyone back to the base chain for no clear benefit and a 20-100x reduction in scalability....This implies a “phase 1.5 and done” approach to eth2, where the base layer retrenches and focuses on doing a few things well - namely, consensus and data availability.