For instance, if there is a reward for a newbie who under few months grew an account to full member without spamming or plagerising, it will in no doubt jealous others to begin to make merit-worth posts.
Jealousy isn't the motivation that will prove helpful. The merit system in itself is enough to motivate one.
In the case of hostile welcome of newbies by older members. I am happy a legendary member pointed out this issue. I believe many, very many new users dropped because of this.
We should endeavour to help and mentor newbies that show inclination to grow and help the forum.
The hostility comes from the years of frustrations of being flooded by arrival of newbies who don't contribute, but just want to know how to get free bitcoin. A lot of newbies ask the same questions over and over without bothering to read the answers, this trait tends to upset some people. The attitude you speak of is not limited to bitcointalk forum, there is no perfect ecosystem except maybe the matrix lol. But if you ever feel like you are repeatedly attacked by the same person you can confront them, or you can use your ignore button. It is your choice
I also wish to suggest if a board like "Skill Acquisition" can be created where people voluntarily teach skills.
There is the service board. We don't need to create a new board for skill acquisition.