While bandwidth might be similar RAM would still outperform the SSD due to the characteristics of SSDs. Specifically RAM is able to instantly update its contents as it is byte addressable whereas an SSD typically requires a read-modify-write cycle due to its significantly larger block size (I think a block for an SSD is 4KB in size).
For example if you need to update a single byte within an SSD block the contents of that block need to be read into memory, the specific byte updated, and then the entire block written back to the SSD. Thus to update a single byte 4KB of data has to be read and then written back to the SSD. RAM, OTOH, can update the specific byte directly without the need to read other bytes. This is not unique to SSDs, traditional magnetic hard disks also had to perform the same read-modify-write cycle as well however the block size is typically 512 bytes instead of 4K.
Furthermore an update to an SSD, unlike a traditional magnetic HD, block typically involves writing to a new location on the SSD. An SSD cannot update an existing location. That location has to be erased first, which consumes time (thus the reason blocks tend to be written to a new location instead of updated in place, it avoids the erase time). If an SSD is nearing capacity there are fewer blocks ready for immediate use thus possibly incurring an erase penalty. SSDs attempt to minimize this by utilizing garbage collection to erase blocks marked as free but not yet erased. However if free capacity is low and write activity is high the SSD may not be able to perform sufficient garbage collection to keep up with the write requests.
That's a 10,000 foot description. While bandwidth might be similar RAM continues to be much faster. But it's interesting to see the bandwidth is similar.
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