Would “Trifles” still hold appeal to modern audiences? Do you feel it was more powerful when it first came out many years ago? What was the most theatrical (most dramatic/interesting) moment in this one-act play to you?

There are a couple of factors to consider when answering the question of Susan Glaspell's Trifles and its continued relevance. First, we have to think about the context in which it was produced. In the early 1900s, women had fewer rights and held a far less prominent position in the culture than they do/can today. Opinions toward women have improved, and more people believe women capable of the kind of insights the women in the play have. The subordination of women to their husbands was more common in the time Glaspell wrote the play, and the condescension of the husbands toward the wives is what Glaspell is highlighting and critiquing. So in some ways, the play may not have the same impact it did in the 1910s.
On the other hand, we also want to consider themes of the play that resonate throughout time and across cultures. Despite strides in gender equality, institutionalized sexism still exists. People certainly still associate particular traits with women and with men. We also know that men are still more likely to hold positions of power in the workplace. Further, universal themes like the arrogance of those in power and the tendency of some to underestimate or reduce the skills of others if they are not the same as one's own are still relevant.
Finally, in my opinion, the most dramatic scene in the play is when Mrs. Hale and Mrs. Peters discover the dead bird in Minnie's sewing equipment. This is the moment of revelation where they realize her motive in killing her husband. The fallout from this moment—their decision to hide the evidence and protect Minnie—is also dramatic and powerful.

The classic play Trifles by Susan Glaspell still connects with a modern audience because the story is compelling and the underlying issues still occur in modern society. While an audience in the early to mid-1900s may have related more to the roles of the men and women in the play, that doesn't stop "Trifles" from appealing to modern audiences.
Though women have more rights and authority than they did when Trifles was first performed in 1916, many people still feel that the two genders don't have complete equality. Beyond that, the battle of the sexes hasn't ended—women and men still struggle to understand each other and put themselves into the other gender's position.
Because of this, the actions of Mrs. Peters and Mrs. Hale, as well as the dismissal of their husbands, still resonates with a modern audience. If it didn't, Trifles would have likely stopped being performed—but it's still a commonly produced play. As a New York Times review of a 2010 production says, "Though the play is celebrated as an early feminist drama, it stands on its own as an engrossing story."
Trifles still resonates with a modern audience because of its storyline. The question of who killed John Wright isn't just a backdrop for a discussion of gender roles and rights, but rather a tale of marriage and murder. The most dramatic moment of the play comes when the women discover the dead songbird that Minnie had wrapped and hidden in her sewing. It's clear to them that John killed the bird and that Minnie killed him in retaliation for that and the way he'd treated her during their marriage. The audience has to wonder how the revelation will affect the investigation—and then discover that the women decide to hide the evidence of Minnie's guilt.
Another moment of extreme tension comes when Mrs. Peters is unable to fit the box with the dead bird into her purse. The audience worries that the sheriff will discover the evidence. Before anyone notices, though, Mrs. Peters is able to keep the box in her coat instead.
While the ignorance of the sheriff and the county attorney may resonate more strongly with a past audience, that doesn't keep the underlying story from being enjoyed by a modern audience. Older audiences may have better understood Minnie's dilemma in her marriage to John; for example, he controlled her clothing, kept her from singing in the choir, and generally dictated every aspect of her life, as the women find when they're searching the house.
Keep in mind that women in America didn't get the right to vote until after Trifles was produced. According to Share America, women gained the right to vote in 1920—four years after Trifles. They also explain that the first woman in Congress, Jeannette Rankin, wasn't elected until 1916, the same year Trifles was first performed.
https://share.america.gov/women-in-politics-timeline/

https://www.nytimes.com/2010/02/02/theater/reviews/02trifles.html