Some relevant forecasts from metaculus are here (mouseover or click to see predictions):
https://www.metaculus.com/questions/3060/when-will-the-first-clean-meat-company-be-valued-at--1bn/
https://www.metaculus.com/questions/3516/will-beyond-meat-outperform-the-the-general-us-stock-market-in-2020/
https://www.metaculus.com/questions/3088/when-will-a-supermarket-sell-a-product-made-of-80-clean-meat-for-3-per-100-grams-or-cheaper/
https://www.metaculus.com/questions/3087/when-will-a-supermarket-sell-a-product-made-of-20-clean-meat-for-3-per-100-grams-or-cheaper/
https://www.metaculus.com/questions/3103/what-will-the-lowest-retail-price-in-usd-per-kg-of-any-product-containing-50-clean-meat-be-in-the-calendar-year-2026/
https://www.metaculus.com/questions/3077/how-much-revenue-will-the-us-market-for-clean-meat-generate-in-the-fiscal-year-2030-in-millions-of-usd/
https://www.metaculus.com/questions/3059/when-will-there-be-a-publicly-listed-clean-fish-company/
Several more relevant questions can be found here.
Some relevant forecasts from metaculus are here (mouseover or click to see predictions):
https://www.metaculus.com/questions/3060/when-will-the-first-clean-meat-company-be-valued-at--1bn/
https://www.metaculus.com/questions/3516/will-beyond-meat-outperform-the-the-general-us-stock-market-in-2020/
https://www.metaculus.com/questions/3088/when-will-a-supermarket-sell-a-product-made-of-80-clean-meat-for-3-per-100-grams-or-cheaper/
https://www.metaculus.com/questions/3087/when-will-a-supermarket-sell-a-product-made-of-20-clean-meat-for-3-per-100-grams-or-cheaper/
https://www.metaculus.com/questions/3103/what-will-the-lowest-retail-price-in-usd-per-kg-of-any-product-containing-50-clean-meat-be-in-the-calendar-year-2026/
https://www.metaculus.com/questions/3077/how-much-revenue-will-the-us-market-for-clean-meat-generate-in-the-fiscal-year-2030-in-millions-of-usd/
https://www.metaculus.com/questions/3059/when-will-there-be-a-publicly-listed-clean-fish-company/
Several more relevant questions can be found here.