It is of course to good a story to be true:

In 2018, a faked snapshot of a UESP page was shared online which falsely stated that, during production of Morrowind, Kirkbride was found under the influence of psychoactive drugs by Todd Howard after being absent from work, paired with a photograph it claimed was taken by Howard of the incident.[49] In truth, no such UESP page ever existed; the story is a fabrication.[49] The image was taken from a music video, fat, that Kirkbride had filmed and uploaded to YouTube in 2013, many years after his time working on Morrowind (the video depicts Kirkbride lethargically overeating as Wesley Willis' I'm Sorry That I Got Fat plays).[50] Lady Nerevar said of the video's misuse, "If you told me that a dumb video we made for fun was going to generate a wholeass conspiracy theory that real life people would ask me about [...] None of that happened in any way, shape, or form".

With regard to the hoax and exaggerated accounts of his writing The 36 Lessons of Vivec, Kirkbride said "You know that comes from a Photoshopped image, right? [...] that’s all a lie. I’ve already given an account of how the 36 [Lessons] were written: a week of bourbon, smokes, and solitude."[52] Kirkbride has repeatedly refuted internet myths that he used recreational drugs[52][53][54][55] and has said that the myths annoy him "more than a little bit".[56] Related rumors that he was dismissed from the company are likewise unfounded; Kirkbride left Bethesda for Zenimax's studio in California,[1] remained involved in the production of Morrowind after leaving the studio,[25] and continued to contribute to subsequent titles.[1][5][9][11]

Source: https://en.uesp.net/wiki/General:Michael_Kirkbride