The problem with relying on maxlength that is built into HTML elements is that they do not work in instances where you are rendering multiple inputs as with the kendo-combo-box. If I set the max length, it sets the max length of the select, which is does nothing. It needs to transfer that maxlength to the input text which is rendered along with the select.

Yes, there are workarounds, but when you are using the controls in an angular mvvm environment where you write little to no jquery, the simplest fix should be to have the control code render the input fully given the information provided.

TLDR:
If given <select kendo-combo-box maxlength="3"
please generate <input class="k-input" type="text" maxlength="3"