As I can see in the latest Alysum update a great work regarding js scripts lazy loading was done. Now the theme load js features only in a moment when it's requested in UI. That make initial theme loading faster
As I can see Alysum developers preparing a lot of improvements in the next update https://alysum.promokit.eu/promokit/alysum-changelog.html And even so far I use Alysum theme it's super flexible and fast, just need to configure your prestashop caching correctly. As for the "Ecolife" the code is...
I'm a developer with experience. I'm using this theme long time. I have checked the network activity and whole code base for such things like you wrote above, but there is nothing about manipulation. Can you show what part of code in what file do the manipulation?