In Destiny 2 there are many ways to earn valuable loot and increase your power level. However, players currently have few reasons to play Strikes, at least according to Bungie. They are not very effective for hunting new loot, and player interest is waning. But that is set to change.
What about the Strikes? Strikes were already an important part of the game in Destiny 1. They are self-contained stories that can be repeated. Strikes in Destiny are somewhat comparable to short dungeons.
In Destiny 2, player interest in Strikes seems to have faded a bit. Many Guardians complete their tasks, such as a daily Strike and three weekly Strikes, to earn the powerful reward, and then turn to other activities.
Bungie is aware of this and wants to make Strikes more interesting for players in the future, possibly with the next expansion Shadowkeep.

What does Bungie say about the Strikes? In a lengthy interview with PC Gamer, Luke Smith and Mark Noseworthy from Bungie spoke about the future of Destiny. Among other things, they addressed the Strikes, which currently provide little incentive for players to increase their power level, as Smith stated:
We want sources of powerful rewards to feel like a major, important, efficient use of players’ time. We want Strikes to always be useful. I think there is a broad recognition in the studio that Strikes are not as useful in the current game as they could be. There aren’t enough reasons to play them.
Smith indicated that the team constantly reviews the various activities in the game through which players can achieve a higher power level. They adjust them to ensure that the things players enjoy the most are also the most rewarding.
These are the reasons why our readers play Destiny 2.

Will Strikes be like they were in Destiny 1? The US site Game Rant speculates based on the statements that Bungie may adjust the Strikes to be like they were in Destiny 1. In the original game, Strikes were a key part of the grind, especially for Guardians who did not regularly participate in raids.
In Strikes, Guardians had chances at specific loot that increased their power level, which was referred to as light level in Destiny 1. In the Strike playlist, players then had to be lucky for the particular dungeon they needed to come up. Because the items, such as specific weapons and armor pieces, were tied to each Strike and could be obtained from chests after defeating the final boss with rare skeleton keys.