Hypocrisy is hypocrisy, regardless of how often it occurs. The definition of the word "hypocrisy" does not change, if it becomes a common practice.
It's not that Republicans wouldn't vote in favor of Merrick Garland's confirmation .... It's that they did not even allow a Senate comfirmation hearing or a vote on Garland to take place. The explanation they gave for this extraordinary step, was that it was too close to the election. They were indeed revealed to be hypocrites 4 years later when they allowed a Senate confirmation hearing and vote to go forward on Amy Coney Barrett, even though it was 6 months later in the year, and less than a month before the 2020 Presidential Election.
Having said that, if this is the historical norm, as you claim? Then name one other time when the exact same scenario has been played out.