How important is drive speed for a MySql server
How many GB in the tables?  It sounds like the RAM might be big enough to cache everything all the time?  If that is the case, the disk is irrelevant.
Even if RAM is not big enough, FULLTEXT does not need to hit the disk that much.  Think of a query as being controlled by how many disk hits are needed, minus how many were avoided by caching.
A Rule of Thumb is that a disk hit on HDD is 10ms; on SSD is 1ms.  If the query needs only a &quot;few&quot; hits, the response time on even HDD will be adequate.
I'm saying that FT 5K searches per minute is probably feasible with your proposed configuration!  Even if there were 20 updates per second.
Every action involving the disk actually occurs in the &quot;buffer_pool&quot; in RAM.  So, if the disk must be hit, the time taken for the query is necessarily slower regardless of disk speed.
On the other hand, NVMe is getting cheap, so why not!