The Manchester Evening News have quotes from the call related to the full year financial results.
Murtough simply states the obvious.
We spent more than we can reasonably afford this summer. He said ""We also saw a higher-than-usual number of departures, and this was an equally important part of refreshing the squad after the disappointing 2021/22 season. We will continue to support Erik in ensuring he has players with the right quality and character to achieve success while
ensuring that investment remains consistent with our commitment to financial sustainability.
Overall, we are ahead of schedule in our recruitment plans as envisaged at the start of the summer, and we do not anticipate the same level of activity in future windows. As always, our planning focuses on the summer window."
United spend 65% of revenue on salaries (65.9% last season, 65.2% the season before). It used to be 50%. Add in cost of host matches, keeping Old Trafford and Carrington in an acceptable state, dividends for Glazers, loan interest payments etc, it doesn't leave that much for transfers.
https://www.manchestereveningnews.co.uk/sport/football/man-utd-transfer-news-january-25081348
https://ir.manutd.com/press-releases.aspx