I have prepared a nice report: the rank of the websites in groups 1..10, 11..100, ... the percentage of TLS and an example of non-TLS website:

https://play.clickhouse.com/play?user=play#U0VMRUNUIGZsb29yK...

    SELECT
        floor(log10(rank)) AS r,
        count() AS total,
        sum(log LIKE '%TLS%') AS tls,
        round(tls / total, 2) AS ratio,
        anyIf(domain, log NOT LIKE '%TLS%')
    FROM minicrawl
    WHERE log LIKE '%Content-Length:%'
    GROUP BY r
    ORDER BY r

    ┌─r─┬───total─┬─────tls─┬─ratio─┬─anyIf(domain, notLike(log, '%TLS%'))─┐
    │ 0 │       6 │       6 │     1 │                                      │
    │ 1 │      61 │      58 │  0.95 │ baidu.com                            │
    │ 2 │     599 │     562 │  0.94 │ google.cn                            │
    │ 3 │    5591 │    5057 │   0.9 │ volganet.ru                          │
    │ 4 │   51279 │   44291 │  0.86 │ furbo.co                             │
    │ 5 │  476181 │  361910 │  0.76 │ funygold.com                         │
    │ 6 │ 3797023 │ 2927052 │  0.77 │ funyo.vip                            │
    └───┴─────────┴─────────┴───────┴──────────────────────────────────────┘

    7 rows in set. Elapsed: 0.844 sec. Processed 7.59 million rows, 43.74 GB (8.99 million rows/s., 51.83 GB/s.)

If I am not mistaken, 8310 sites offer http and https:

    grep -o -E "://.*?," current.csv | sort | uniq -c | grep -v "1 ://" | wc -l
    8310

How about websites that are browsed http first and then redirected? People might browse for a domain without the https prefix for convenience (or old links) and the browser defaults to http.

“The 5% rule”