With regards to AMD: SystemJS is a polyfill for the ES2015 module loader designed to remain a set of plugins to said module loader should a browser actually start to implement it. The plugins include the ability for the ES2015 module loader to directly load AMD and CommonJS modules, thus none of the legacy AMD is technically lost and you also don't necessarily need something like Browserify/Webpack in a build process or Node-style modules (CommonJS). JSPM is a package manager for SystemJS and for the most part it can be fairly straightforward to move from Bower to JSPM.
With regards to Typescript: I don't think it is a "dead end" and I definitely think you are wrong about the future of it. Typescript has been relatively careful at keeping "an eye to the horizon" and having some idea of the "forward compatibility" of its features. For instance, the module format in Typescript was built before the ES2015 standard finalized, but the final standard was surprisingly close to what Typescript used and nothing necessarily required being rewritten and it was very easy to clean up the old style incrementally if you did feel like being particular about using the final ES2015 syntax. I feel like the same can be said about Typescript's type annotations. They are definitely informed by ES4 ("the lost version", what forked into ActionScript, sort of) and in turn, yes, the Typescript team is certainly influencing the standards to possibly add type annotations to the EcmaScript standards ("this time for real"), or at least a Python 3-like approach where type annotations are safely ignored by browsers when left in the code.
At the very least, if ES standardized type annotations are suitably different from Typescript there will presumably be a Typescript transpiled output to it (just as the old Typescript module imports get output correctly when targeting ES2015), and you can even use that output to bootstrap your conversion to the new syntax (thanks to Typescripts attempt to remain a pure superset of ES).
With regards to Typescript: I don't think it is a "dead end" and I definitely think you are wrong about the future of it. Typescript has been relatively careful at keeping "an eye to the horizon" and having some idea of the "forward compatibility" of its features. For instance, the module format in Typescript was built before the ES2015 standard finalized, but the final standard was surprisingly close to what Typescript used and nothing necessarily required being rewritten and it was very easy to clean up the old style incrementally if you did feel like being particular about using the final ES2015 syntax. I feel like the same can be said about Typescript's type annotations. They are definitely informed by ES4 ("the lost version", what forked into ActionScript, sort of) and in turn, yes, the Typescript team is certainly influencing the standards to possibly add type annotations to the EcmaScript standards ("this time for real"), or at least a Python 3-like approach where type annotations are safely ignored by browsers when left in the code.
At the very least, if ES standardized type annotations are suitably different from Typescript there will presumably be a Typescript transpiled output to it (just as the old Typescript module imports get output correctly when targeting ES2015), and you can even use that output to bootstrap your conversion to the new syntax (thanks to Typescripts attempt to remain a pure superset of ES).