In my opinion she should’ve had her own trilogy,
The trilogy should’ve been
• Black Widow (2012) right after The Avengers - But about her origin story at the Red Room
• Black Widow 2 (2016) How she met Clint/ and joined S.H.I.E.L.D. / Also the Budapest mission happens
• Black Widow 3 (2021) The final movie that we actually got where she meets Yelena, Alexie and Melina again after over 20 years/ and finally takes down the Red Room and General Dreykov