If “senior applicants” is defined as years worked in the industry, then I do not agree that most senior applicants are expected to be elite. Most senior applicants are also not expected to be managers.
Based on my personal experience, experiences of others I have spoken with at different companies, and what I have read; tech companies are more likely hire for managerial positions from within rather than externally. This contributes to managers tending to have more years of experience at that same company than technical track types.
Regardless of whether hiring externally for managers, companies generally do have hires targeting experienced employers, rather than just looking for new grads. These experienced hires are often for technical positions, looking for a particular combination of experience and skill sets that is rarely found in new grads. However, this senior external hire with desired skill set doesn’t necessarily mean he/she is “elite.” Many companies regularly hire experienced tech (non-managerial) employees with desired experience and skillset, who show little indication of being “elite” (defining “elite” as top % ratings), compared to other employees at that company.
I agree that the percentage in managerial roles tends to increase with years worked in the industry, as well as the percentage spending a portion of their time on managerial tasks in addition to spending the bulk of their time on technical tasks.