Why did The Looney Tunes Show change Lola's personality?

Initially, she was created for marketing in the 90s. A lot of people remember her as an important character from the movie, but when you rewatch Space Jam, she has about 5 minutes of screen-time, and she doesn't really speak much past her initial introduction. Bill Murray had more screen-time than her, but she left an impression and her merch certainly did sell.

I would imagine they made the change because she was "too sexual" in the movie. The 90s was an entirely different era, and what worked in shows back then won't always work as times change. Look at the original antics of Bugs Bunny himself from the OG Looney Tunes (Merrie Melodies) shows, and you will see a very distinct difference between how Bugs himself behaved back then compared to how he is in TLTS. However, that alone might not justify or explain the entire change of Lola's character.

For instance: she could have gone from sexualized to a strong and silent type of woman with hidden sports skills and she still would have been appealing to the show's intended audience - perhaps even better for them. This is the direction that I personally would have taken; but then there would have been 2 no-nonsense female love interests for the main characters (Bugs and Daffy), and when writing any show, that tends to make things boring and could even be mistaken for a lack of creativity or trying too hard to kiss-up to a female audience. Diversity of character personality is important for writing entertainment, after all.

They could have made a new bunny character for this (Lola's) new quirky personality concept, and let Lola be a cameo only by Bugs perhaps mentioning an ex-girlfriend who became a basketball star, but the TLTS Team already had a female rabbit (Lola) on the sidelines, so instead, they retconned her entire persona. The industry will normally avoid wasting resources, especially when it involves a character who was popular and sold merchandise prior to the recycling of their concept.