Sanctuary of the Holy Shield (0.9% pick rate)
In this area, Teamfight Tactics players will receive a Demacia Crown that grants healing or attack stat boosts for champions. This stat will change depending on whether the champion is placed in the front line or back line. The unique aspect of the Sanctuary of the Holy Shield is that if the champion holding the aforementioned item is defeated, the Teamfight Tactics player will lose the match immediately.

The reason the Sanctuary of the Holy Shield has a low pick rate lies in the Demacia Crown item itself. Gradually increasing healing or attack stats is not as beneficial compared to other items. In return, players can be defeated immediately if the champion holding this item is taken down. Clearly, this is a very risky move that most players will avoid.
Stillwater Camp (0.9% pick rate)
Stillwater Camp in the League of Legends lore is where the prison for criminals from Piltover and Zaun is located. Therefore, when introduced in Teamfight Tactics, the effect of this area is that Tech Cores will not appear in the match.

It is important to note that in Season 9, all Legends provide players with certain Tech Cores to influence their play style. The inability to select this at Stillwater Camp can leave players feeling lost when choosing their team composition. As a result, this area has the extremely low pick rate mentioned above.
Sewage Pit (1.1% pick rate)
In this area, players will not receive interest income but, instead, will gain an additional 3 gold each round. This effect will completely change the economic gameplay in the match as holding gold for interest becomes meaningless.

Basically, regardless of the team composition, holding gold for interest to accumulate wealth is always crucial. This has been a practice throughout many seasons of Teamfight Tactics, becoming a habit for players. Therefore, when encountering an area with effects that contradict this habit, like the Sewage Pit, it will naturally be overlooked by players.
Conclusion
With effects that do not align with player habits, areas like the Sanctuary of the Holy Shield, Stillwater Camp, and Sewage Pit are experiencing extremely low pick rates. Unless Riot Games makes any significant adjustments, these areas are likely to continue being “ignored” by players in the future.