Lest we forget, making cybersecurity impenetrable is an aim with huge potential ramifications.
The US position until now is not to provide such security to the public. Practically-speaking, permitting fairly good but imperfect security is the current US political position. The imperfection is what the intelligence services use to keep an eye on bad actors. Strenth of encryption is what the US government complained about when Apple seemed to have developed a protection model the US government couldn't breach. Law enforcement operates on a reasonable standard, following the fourth amendment. Terrorists and dictators want impenetrable security.
So Trump just changed this without even thinking about it in a meeting with Putin.
If he had had someone who knew anything in the room with him, he wouldn't have made such a gaffe. At least, he should have considered the impact.
For Putin, this is a triumph. He took down the rube.