Does it really matter to know the behavior of these variant spiders to enhance the SEO effects?

If you have better knowledge of how search engine spider works then you will get better smartness in your SEO efforts. Spider works according to algorithm and knowing the behavior of spider means knowing the working model of algorithm. The websites get up and down in search engines according to the sequences of algorithm. So, having knowledge of spider's behavior is really very worth matter.

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Thank you for the information.

It is not actually. Spiders only collect data and transfer it to se db. If you show different to spiders than visitors then it is not recommended any way.

Yes we must be aware of the spider's and crawler's behavior and then change our  SEO strategy accordingly.