Excel to Power BI

Yes. In overview:
1. Load the data that pivot table is based on into Power BI. Not the pivot itself, the raw data.
2. In the Power Query stage, apply the same filters as are on your pivot.
3. Use Group-By in the Power Query stage to pivot your data. Group on [Application Tier], [Response SLA Met] and [Priority]. You will not have a column per priority. This is fine. It's all in rows instead.  It should automatically add a count column for you, called [Count]
4. Close & Apply
5. Use 'Enter Data' to create a one-column table with four rows. Call it 'tblPriority', call the column [Priority], the data is Sev1, Sev2, Sev3, Sev4
6. In your model, join the [Priority] columns together
7. Create measures, for example:
Count Met = CALCULATE(SUM(tblData[Count]), tblData[Response SLA Met] = "Met")
8. Create a matrix visual. Drop the [Priority] column from tblPriority into Rows & your measures into values.

Feel free to reach out if you need more detail.