This is interesting and detailed analysis, although I think you should use some qualitative interviews to validate your data findings.

I asked a handful of my trading buddies who use DEXs whether they had a DEX loyalty, and only one said they did. The rest use multiple ETH accounts, and generally use a different browser (with Metamask) to access different DEXs.

Also, new tools like Totle, which fulfill orders from a host of different orderbooks complicate the situation further!