Roadblock is a type of game mechanic that blocks player action until he commits to spend resources(effectively blocking gameplay: it is an anti-pattern).
Typically the roadblock is also a resource-sink, designed to drain player resources in exchange for rewards(e.g. consumable keys), or simply block access to parts of game until requirements are met(e.g. locked door)

Components of roadblock:
1.Locked Reward(e.g. a locked treasure chest,locked door,item with specific requirements):the player's target when he encounters the roadblock.
2.Key: Specific resource/item/skill/stat required to unlock Reward.
3.Resource(e.g. gold,stat points,level):Resource required to obtain key.

The problem with roadblock mechanic isn't realism, its the interruption in flow of the game.
It also creates basis for micro-transactions(key for treasure chest bought with cash) and lootboxes(random rewards).
Identifying/Eliminating roadblocks and simplifying the flow of gameplay increases fun and immersion.

Solutions to roadblocks:
1.Partial:Eliminating the key for Locked Reward mechanic and use resource cost(e.g. opening a locked chest cost 100 gold).
2.Synergy:Key is not absolutely needed but increases reward(e.g. stat requirement for items replaced by stat-synergy modifier on item).
3.Full: Eliminating the "locked" part of the reward. Solves the problem entirely(e.g. chest is always unlocked, items are free to use anytime, door unlocked).