The ending of that play was too soapy, it felt unrealistic.

soapy 是形容词，由名词 soap（肥皂）加上后缀 -y 构成。soapy 本义是"像肥皂的"或"含有肥皂的"，但在比喻用法中可以表示"过分煽情的"或"夸张做作的"，类似于肥皂剧（soap opera）中常见的那种过度戏剧化的情节。