Although the best solution is to create the SQL server view, If you cannot do that for any reason, try filtering the data in power apps by using some column in your table. I was having a similar issue with a large data set and this is the way I resolved it:
I had a Sharepoint list named 'Customers' wich had 2000 items (meaning 2000 records). This list had the following columns: ID, LastName, FirstName, Lastfirstname.
I had a drop down list in which I needed to search for a customer by LastName, FirstName. In my particular case, I was using my previously concatenated column 'Lastfirstname', so I was using this column in the drop down list, but it was not showing me the customers created after record 500. So this is what I did:
1. I inserted a Text input field and named it 'Lastnametxt'
2. Inserted the drop down list and selected the Sharepoint list 'Customers' as datasource for this drop down list
3. Selected the column 'Lastfirstname' as the column the drop down will search into
4. Then in Advanced > Data > Items I inserted this formula: Filter(Customers, LastName = Lastnametxt.Text)
So with this, the user can put the last name of the customer in the text box and then go to the drop down and it shows the customers filtered, even if they are above the record number 500.
You can do this also using a combo box and that way you won't need the concatenated column (By the way, I really don't know if it is possible to concatenate columns in Sharepoint, I created my concatenated column in Access before exporting the table to Sharepoint)
