Maybe another technology will appear that could rival SPVP (SNARKS?) but I should say it is in fact merged-mining that enables the protection of miners' economic incentives
Here's the thing, these miner's economic incentives are also what subverts the security of MM SCs.
The problem here is that SCs
are expected to be valuable.
To paraphrase Peter Todd, merge-mining without majority, (or at least near-majority) hashing power of the whole pool of the miners compatible with doing so...an attacker can 51% attack the SC at negligible cost by re-using existing hashing power.
Namecoin is exceptional because it is a time-stamping service that is a mere public good and perhaps more importantly, not profitable. So without money involved, the economic incentive to attack it would come from competitive forces (ICANN? LOL!).
Dogecoin-Litecoin? Another exception. Dogecoin is just the cutest of all the crypto currencies. So charity, much wow. People won't like you much for kicking a dog when its down. SCs are about the money/assets/privacy, so they have no such immunity. They are more attractive targets, and potentially much more lucrative.
To release a SC MM'd with Bitcoin, it should be launched with near complete acceptance by the entire mining community of Bitcoin. (and getting that requires both centralization of mining, and trusting the centralized controllers)
MM is a trade-off. With merge mining you get protection against all the externals to crypto, in exchange for vulnerability to all the internals, the ASIC armed Bitcoin miners. It is a delicate balance as to which is the greater risk. Furthermore, the incentives to attack should be expected to shift as a SC gains value or if a large number of BTC get locked into the SC. The economics and vulnerability profile are much less simple than you make it sound.
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The cynic in me would consider whether all the trolling you are doing here is for the benefit of the Blockstream investment pool to get some low-cost Due Diligence work out of us. The sort of analysis you are getting from some of the folks here is pure gold.