Fact check request: Were the Buddha and his clan formerly Śiva worshippers?

Recently I have come across A Social media post which happens to be circulating across several platforms that claims Siddhārtha Gautama and the Śākya clan were originally devotees of Śiva i.e, followers of Śaivism before abandoning this earlier religious affiliation and later embracing Buddhism. The post also cites various textual sources in support of this assertion. ---------- Enquiring From a purely academic perspective grounded in the scholarly study of early Buddhist history :- 1. I would like to know whether the sources cited are authentic and whether the conclusion presented in the post is accepted by mainstream scholars of Buddhist history. 2. Additionally, do the Nikāyas, the Vinaya, or early non-Buddhist sources provide any indication of Śaiva devotion by Siddhārtha Gautama or among the Śākyas? Seeking a Proper fact-based assessment grounded in proper citations of primary sources and established academic research. ----------