Is it worth buying JR Pass?

Hello,

Will be travelling to Japan on January 21 to 31. And will be visiting the following:
#Activities 1/21/2025 KIX to Nest Hotel Shinsaibashi
1/22/2025 Universal Studios Japan
1/23/2025 Explore Osaka: Osaka Castle, Umeda Sky Building, Shinsekai
1/24/2025 Morning- Kyoto, Uji, Afternoon- Nara, then Travel to Nagoya
1/25/2025 Go to Shirakawa-go, Takayama Old Town, travel back to Nagoya or Takayama
1/26/2025 Travel to Nagano, Jigokudani Monkey Park or skiing, relax at onsen
1/27/2025 Travel to Tokyo, Ghibli Museum
1/28/2025 Tokyo Disneyland
1/29/2025 Tokyo DisneySea
1/30/2025 Explore Shibuya, Meiji Shrine, Akihabara
1/31/2025 Departure

In summary we will be in OSAKA for 3 nights, 2 nights in Nagoya, 5 nights in Tokyo. I am having a hard time estimating the costs of the tickets due to the complexity of the railways and the lines that will be used for each travel. I know that by availing the rail pass will make it easier for us to manage this. But I think that buying separate tickets will be cheaper, am I right?

Thank you in advance for reading and helping me with this.