Kinda, keeping in mind that the shared-8x is 8 cores and performance-1x is 1 core.
Multi-core applications will suffer with only 1 core when using performance-1x, but on the other hand if those Multi-core applications utilize more than 6.25% sustained CPU utilization per core then you’ll quickly be throttled when using shared-8x.
The difference really is how long you can maintain a sustained load. Shared is limited to 6.25% while performance is limited to 62.5%.
The credit system is similar to what’s used in other clouds like the GCP Shared Core instances or the AWS T3 instances. It allows for exceeding the load limits in time limited bursts which can be gained through time that your load is under the limit.