Not really. The max you would lose from your TH is 200k as a TH10, and you'd be assured of a shield at that point. TH has 5000 hit points. 2 Storages have just over 4000 combined hit points (currently worth 200k when TH10 has max available).
If you are protecting your TH, and get 2 starred, it's likely you're going to have lost some storages anyhow. I lost 200k on losing 2 storages last night with a <40% defence I didn't get a shield. And yes, it's a punishment for being 2-starred, but reward for protecting your TH too (since now players can only get 50% of your available storage loot if they can't get to your TH).
It would certainly help promote TH protection, that's for sure. If it's just 50k in TH, I think many would take that tradeoff easily, especially at TH10 for a shield.
And I didn't really mean to include the DE in the TH storage too. If you did I guess, it'd help protect some against the Lightning. Anyhow, I'm just playing around with numbers. Maybe less would be sufficient, but just something to help promote actual defences, and stop the bleeding from people that do actually defend and win those defences without getting shields. I'm welcome to all suggestions, I just think the game should change the incentives (as in, actually create some for the majority of players) to actually defend their base.

