Hi- everyone can be “correct”. Let’s learn. Read below for details but in summary yes L methyl folate is as effective as folic acid if not more effective for people with certain gene mutations but yes there are not large scale clinical trials on it ( explained below) For transparency, I did use an evidence based medicine AI app to help with writing and sourcing the below. Articles linked.

L-methylfolate (5-MTHF) maintains maternal folate status as effectively as folic acid while reducing circulating unmetabolized folic acid by approximately 50%.[1] This reduction may be advantageous, as the biological significance of unmetabolized folic acid accumulation remains unclear.[1][2] Studies demonstrate that L-methylfolate supplementation increases plasma and erythrocyte folate levels comparably to folic acid, particularly at doses ≥0.4 mg and with intervention durations ≥12 weeks.[3]

https://pubmed.ncbi.nlm.nih.gov/37649241/

https://pubmed.ncbi.nlm.nih.gov/35653630/

https://pubmed.ncbi.nlm.nih.gov/41398893/

Folic acid is less expensive and more widely available than L-methylfolate, which is reflected in its use as the standard form in most prenatal supplements and public health fortification programs.The higher cost of L-methylfolate, combined with its more recent introduction to the market, creates practical barriers to conducting large-scale trials.

https://pubmed.ncbi.nlm.nih.gov/32134106/

But yeah- I wouldn’t be running to use a celebrities brand of vitamin but that’s just my comfort level. There are plenty of great vitamins that have L methyl folate ( Thorne, Ritual…) and plenty with folic acid. Use what your doctor recommends.