Parameters are one of the most dynamic tools in Tableau, however, using them often requires multiple workarounds and results in a poor user experience as measure/chart labels do not update based on parameter selections. The screenshot below (Ex. 1) is just one use case where a chart would be much less confusing if the axis names and legend could update to use the parameter value. This applies in a similar situation when using text tables and the columns/ row label does not update with the selected parameter value.
Could you please add a feature to input the selected parameter value into titles (and like use cases)? I imagine it would be similar in functionality to entering a custom value for a reference line label (except with the parameter value rather than the parameter name). Screenshot below (Ex. 2).