That is at the higher-end of revenue and scale! I think you'd typically see Shopify as the integrated solution for <$5-10M companies, big enterprise solutions (Adobe, SAP, Oracle) for $100M+ scale, and solutions like Fabric trying to find a middle spot in that range.
Vendors like Toshiba[1] are starting to offer some forkable microservices/APIs that let you control your destiny on development while also giving you an architectural headstart so you don't rediscover the e-commerce domain from first principles. (But it does usually mean you're committing to spending money on POS hardware - may be an assumed cost in some omnichannel use cases.)
At a certain point, you need to ask yourself how much digital is a competitive differentiator for your business. It's increasingly tablestakes in B2C with B2B not far behind, and the SaaS/platform solutions will indefinitely saddle you with sales-driven SIs and upgrade cycles if you don't bring those capabilities in-house. It's pretty difficult to do rapid, customer-centric iteration with Adobe Experience Manager or similar low-code front-end platforms.
For teams that are trying to bring more in-house, you can do a custom build or cobble together solutions but hopefully your e-commerce org has product and technology leaders who know the domain from previous experience or you're in for a long learning curve!
[1] https://commerce.toshiba.com/wps/portal/marketing/?urile=wcm...