This isn’t only namecheap. Porkbun notified me about it a couple of weeks ago:
Verisign — the registry behind .com and .net — is set to increase wholesale pricing on .com domains industry wide on September 1. This has become an annual trend, and we expect the .com price will steadily increase through 2029. This increase affects every registrar that offers .com domains, not just us.
Namecheap ups its prices 9% for .com and .xyz this fall. (lemmy.ml)
Having just jumped from Google to Nameheap this is more than mildly frustrating....