Can anyone explain why rollups do not seem to be a good scaling solution?

To be honest, I have done a fair amount of reading on rollups but still don't understand exactly how they work even in practice. Here are a few questions I have:

First of all, even though rollups are supposedly part of Ethereum, the process of getting tokens onto and off of a rollup chain is cumbersome and usually expensive. When I have Arbitrum ETH I do not have Optimism ETH or L1 ETH. Maybe I have the equivalent amount of value, but if I want to use a dApp that supports a different rollup or is still on L1 I'm out of luck. That requires bridging my assets once or maybe twice and costing me fees that I wouldn't have incurred if I just stuck with L1 and ate the fees there. Question here is, will my L1 ETH eventually be able to be used on a rollup natively? Or will I always have to keep bits of ETH and whatever other tokens I'm interacting with scattered across different rollup chains for use with different dApps?

Secondly, since rollup chains are EVM compatible, why is it taking so long for dApps to migrate their services onto rollups? Some projects don't even act like it's a priority, and I rarely hear people asking questions about when they'll be able to actually utilize these dApps on a rollup. Instead people are very willing to jump ship to Solana, etc. for a better experience. It's very possible I'm just impatient, but when should I expect the Ethereum network at large to actually be utilizing rollups (for things like ENS, OpenSea, Audius, etc)? I'm aware that OpenSea supports Polygon, but then instead of buying an Ethereum NFT you'd be buying a Polygon NFT that doesn't show up on Ethereum. Might as well use a different L1. Will all rollups work like this?

Any responses welcome, thanks for reading!