If there is one great positive I can state regarding Gem’s monetization is that they are extremely generous with their premium currency income for long time players.
Being in a guild that can clear all tasks and having kingdoms somewhat capped I’m easily able to buy tier 4 weekly events and some random tiers for pets/faction assault/weekend events and daily/arena offers and still have a net positive at the end of the week, even enabling me to splurge on the monthly new delves to buy potions of Power. And I don’t collect that many tributes (definitely the main source of gems).
So for sure, daily offers are more enticing for high level players and not something that a new player should worry about but at least gem income is only blocked by game progression that can be overcome solely with time played and not behind some crappy VIP level or other mechanic that would require monetization.