There was a period in time where Verisign would have been an easy 65%+

https://www.keyfactor.com/blog/broken-trust-symantecs-untrusted-verisign-root-ca/

Using the top 1250 The Majestic Million, and whatever powershell on a windows desktop could connect to on 3/20/2025.

https://majestic.com/reports/majestic-million

Total domains processed: 1250
Successful HTTPS connections: 1174 (Comcast USA residential Subscriber)

Certificate Authority Statistics:
Let’s Encrypt: 250 (21.29%)
DigiCert Inc: 217 (18.48%)
Google Trust Services: 212 (18.06%)
Amazon: 149 (12.69%)
GlobalSign nv-sa: 109 (9.28%)
Sectigo Limited: 61 (5.2%)
Internet2: 37 (3.15%)
GoDaddy.com: 24 (2.04%)
Entrust: 19 (1.62%)
Microsoft Corporation: 14 (1.19%)
DigiCert: 12 (1.02%)
Certainly: 11 (0.94%)
COMODO CA Limited: 10 (0.85%)
Apple Inc.: 7 (0.6%)
SSL Corporation: 5 (0.43%)
Gandi: 4 (0.34%)
GEANT Vereniging: 4 (0.34%)
WoTrus CA Limited: 3 (0.26%)
Cybertrust Japan Co.: 3 (0.26%)
ZeroSSL: 3 (0.26%)
IdenTrust: 3 (0.26%)
Network Solutions L.L.C.: 2 (0.17%)
Starfield Technologies: 2 (0.17%)
China Financial Certification Authority: 2 (0.17%)
Deutsche Post AG: 1 (0.09%)
McAfee: 1 (0.09%)
Actalis S.p.A./03358520967: 1 (0.09%)
Japan Registry Services Co.: 1 (0.09%)
TrustAsia Technologies: 1 (0.09%)
Certera: 1 (0.09%)
DHIMYOTIS: 1 (0.09%)
Hellenic Academic and Research Institutions CA: 1 (0.09%)
Smile: 1 (0.09%)
CLOUDFLARE: 1 (0.09%)
sslTrus: 1 (0.09%)