First of all, the pre-history of Buddhist statues is much earlier than that of Taoism. In fact, Buddha statues were not respected in the early days of Buddhism. Sakyamuni opposed idolatry before his death, so there was no tradition of carving Buddha statues after his death for hundreds of years. But around A.D., that is, during the Guishuang Dynasty, Mahayana Buddhism began to expand. Compared with primitive Buddhism and Buddhism, Mahayana Buddhism absorbed the idol worship tradition in ancient Greek civilization and began to carve Buddha statues on a large scale.
Therefore, from the beginning when Buddhism was introduced into China, there was a tradition of depicting Buddha statues. In Mahayana Buddhism, depicting Buddha statues is a kind of kindness, so believers are eager for this kind of behavior. In addition, the Southern and Northern Dynasties and the Sui and Tang Dynasties after that were the rapid development and heyday of prehistoric Buddhism in China, so a large number of Buddhist grottoes were formed at this stage, including many large Buddha statues, and the Leshan Giant Buddha in Sichuan is a good proof.
Secondly, the differences in religious concepts have also caused different attitudes of the two major religions towards the construction of grottoes. Both Han Buddhism and Buddhism will build grottoes for good deeds, so both monks and believers at home are doing their best in this respect. On the other hand, Taoism does not regard building grotto statues as an important way to accumulate virtue and do good deeds, and obviously lacks satisfactory religious internal incentives for this behavior.
Thirdly, from the perspective of the prehistoric development of the two major religions, the main reason is that Buddhism has distinct grades, perfect ideas and is very active in attracting believers. Taoism pays attention to quietness and has a threshold for accepting disciples, which will inevitably lead to the lack of financial resources of Taoism, which also makes Taoism lack the financial support of Buddhism when carrying out large-scale religious projects such as carving Buddha statues.
Finally, there are still large-scale gods in Taoism, but generally speaking, Taoism is obviously inferior to Buddhism in distribution, quantity and artistic achievements. As for recent years, many land gods cast by modern technology are no longer purely religious acts, but commercial acts, and their connection with religion is no longer great.