Google and Linkedin does have designed the systems which support millions of transactions/sec, and also there is Netfilx which uses microservices to support its vast streaming services. Following their path, there is always the temptation to build such a robust and fault tolerant system with the same level of user support, but is it really required? Such systems are complex and costly to maintain and support. The business use cases often do not require to have such huge and complex systems. If required, Inflatable Microservices Architecture is one such approach which helps to create microservices which are for normal loads and could be inflated for high loads, and thus keeps the running cost low. To implement this technique just requires two principles to be followed while designing the application architecture, first is Module Code and Monolithic deployment and the second principle is to use swappable modules to emulate microservices. And when required, simply dirty scaling could be used to inflate the services and the application will be started in the new clusters.

A good article explaining this: https://medium.com/swlh/designing-inflatable-microservices-architecture-9976e63ad820