I agree.  The worst is the roll out of this doesn't appear to have happened to all of us at the same time so it's not a "feature improvement" in the classic sense where everyone is "upgraded" to the new version of QuickBooks Online.   

It just started doing this today 6/22/2020 for me.  There tech support said it happened months ago, which based on other posts, it did to others as early as March 2020.

Others have documented the workarounds for cutting checks, which are to 1) make them from the expense tab (you will still see Make Payment there) or 2) Select Mark as Paid (however, really does this signify Make Payment to you? This wording makes me want to avoid clicking it if I want to cut a check! 3) If you are tricked into clicking Schedule Payment, you will be greeted with marketing for the Bill Pay which in very small lettering  says "You’ll be asked to opt in to “Bill Pay”.  

It seems to be designed for a user to accidentally sign up to this Bill Pay Service.  I recall about a year ago a similar Opt-In features for a more expensive version of QuickBooks Online (Advanced I believe) which had similar mod-of-operation.

None of this seems to be necessary QuickBooks, you have good software and support and are raising your fees frequently  so why this? It makes users unhappy and makes us start to question the use of the product.  Marketing driven changes like this that take time away from other tasks to figure out how to make something work that did so just a "feature" ago really is annoying to business owners and employees who are doing the accounting.