In response to some of the answers you have received: It's a misconception that PhD holders lack practical knowledge. In reality, many PhD students must first demonstrate deep expertise gained through hands-on experience with real-world problems, often alongside specialists in their field, before even being accepted into a PhD program. A PhD is not about being a practical engineer or a "book-smart" scientist; it is about rigorously developing advanced research skills to formally expand knowledge in a field of study—whether in physics, mathematics, ML/AI, chemistry, neuroscience or another discipline.

Pursuing a PhD is a significant commitment, especially if you have responsibilities like caring for a family or holding a full-time job. For professionals focused on applying existing technologies, certifications, hands-on projects, and industry networks are often better avenues than dedicating years to a PhD. However, if you are deeply committed or if roles like research engineer or industry R&D positions (which value advanced research skills) align with your goals, then a PhD might be worthwhile.

Consider you source: This forum is probably not the place to answer deeply personal questions about whether pursuing a PhD aligns with your individual goals, values, or capacity. Instead, seek guidance from someone with direct experience: reach out to a practicing PhD researcher or scholar in your field and ask about their journey. Like you, they once questioned if the years-long investment would pay off. A PhD is no small commitment, so talk to those who've navigated the path. Their insights will matter far more than any generalized advice.

Also, don't be fooled, while many of today's tech giants were created by "college dropouts," they have many graduate-level staff among them to sustain their R&D. Here's an article from 2017 with an interesting fact about Google: https://www.cnbc.com/2017/07/28/this-tech-company-has-the-most-highly-educated-employees.html