Is Kiyomizu-dera ever empty?

Essentially, no. The best you can do is arrive at 6:00 AM, but even then, there will be professional photographers and early-bird groups.

Can I use a taxi to avoid crowds?

Taxis are helpful, but they get stuck in traffic just like buses. Walking or renting a bicycle is often faster during peak spring/autumn seasons.

How to Beat the Crowds in Kyoto’s Temple District

The secret is extreme timing: arrive at major sites by 7:00 AM or wait until the final hour before closing. Focus your exploration on the Northern Higashiyama area rather than the saturated Gion or Kiyomizu-dera corridors.

Master the 7:00 AM start. Most tour buses arrive at 9:30 AM. Be at the entrance of popular spots like Eikando or Ginkaku-ji at 7:00 or 8:00 AM to get 90 minutes of silence before the crush begins.
Head North. Avoid the Southern Higashiyama tourist trap entirely. Take the bus to Northern Higashiyama, where temples like Shinnyo-do and Honen-in are free or low-cost and rarely have more than 10-15 people at a time.
Use side streets for transit. Do not follow the main thoroughfares like Higashioji-dori. Use the parallel residential alleys to move between districts; they are quieter, scenic, and offer a better look at local life.
Visit on weekdays during off-peak seasons. Avoid the cherry blossom (late March/early April) and autumn leaf (late November) windows if you want true solitude. Aim for mid-May or early October for the best balance of weather and crowd levels.

Is Kiyomizu-dera ever empty?: Essentially, no. The best you can do is arrive at 6:00 AM, but even then, there will be professional photographers and early-bird groups.
Can I use a taxi to avoid crowds?: Taxis are helpful, but they get stuck in traffic just like buses. Walking or renting a bicycle is often faster during peak spring/autumn seasons.