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I'm not ignoring that at all:
Obviously a PWA wallet for pocket spending money is not as high-value a target as the base-layer bitcoin node software, but that argument only works for as long as the sum value of money stored in that wallet across all users remains small. If any wallet gets popular enough, even with very small individual balances, the wallet software and distribution pipeline will eventually become a desirable target.
From the perspective of a user, yes, by all means store pocket change however you want if you feel the risk is acceptable. That's the same reasoning why I think ecash wallets in general have great potential.
Yet, in a perfect world with all else being equal, a rational user should always choose a native wallet software over a PWA wallet on the basis of security alone, perhaps with one or two rare exceptions like an untrusted-dev scenario.
That's why I would urge developers to ship their wallets as both native apps and PWAs. Let users decide for themselves how secure they want to be.