Interesting video.
I already use HA serum in my skin care, i alternate between HA and a vitamin C serum. I was recommended it by a friend who is a dermatologist, i just follow his advice with no knowledge on the science (i trust him not to give me bad advice and ruin my face haha).
Even with my simple regime i've noticed really good results, following it morning and night for 6 months so far:
1. cleanse with a good face cleanser, dove sensitive skin soap is a cheap option that works well,
2. a couple of drops of serum on dry skin, I alternate HA and a vitamin C serum for morning. The brand 'The Ordinary' makes great reasonably priced options,
3. moisturize with a light non-oily moisturizer,
4. Sunscreen, this is a must every day to prevent damage from sun and pollutants, something light and non-oily. I like 'La Roche-Posay' because it is anti-shine and non-perfumed.
I went down a path of buying the expensive brands for a while, but i honestly didn't see any benefits over the cheaper brands like The Ordinary