Have some friends also working in a somewhat adjacent space (Audienceful) so will be watching you guys closely.
But in general it seems email is pretty crowded these days and a lot of the sub-niches are also pretty crowded (eg. Klayvio in ecomm, Customer.io in Saas, Substack/ghost in newsletters, Convertkit for wordpress bloggers, etc).
And for the most part all these apps are just sending on the big API-based senders under the hood (Eg. Amazon SES or Sendgrid). Even the newcomer API-based senders like Resend are just a wrapper around Amazon SES. Which makes any claims around differentiated deliverability on any email platform dubious at best.
Is the plan to build your own sending infra long term?