Your engine is using a quart every 1000 miles. More than it did when new, but not excessive by many companies, especially with 173K on the clock. Toyota doesn’t think this is an issue because it is your issue for using the low oil minder instead of actually checking the oil regularly.
You have 2 choices here.
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Check your oil FAR more often than you do now (and add as needed) because 2 quarts low is BAD. If you keep doing that you will destroy the engine.
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Install a rebuilt engine because yours is worn enough to use a quart every 1000 miles.