Do I need to lock the PCIe link speed if my Samsung 9100 PRO 4TB is lagging while loading high-res MODs in Cities Skylines 2?

Once my city hit a million residents, the immersive experience was constantly ruined by these endless loading bars, which was incredibly frustrating. The data showed that the Samsung 9100 PRO 4TB's PCIe 5.0 link was flipping between Gen4 and Gen5 in 'Auto' mode, causing random read performance to swing wildly between 40GB/s and 60GB/s. I tried updating the storage drivers, but it only shaved off about one second—basically useless. I went into the BIOS, forced the M.2 slot to Gen5, and set the power plan to 'Ultimate Performance'. CrystalDiskMark then showed a rock-solid 12000-12500MB/s sequential read, and my load times dropped from 25 seconds to 14 seconds. I did have two random restarts under full load after locking Gen5, but a tiny tweak to the motherboard VRM voltage (1.2V) stabilized everything. The drive temp sat between 55-62℃ with a perfectly smooth read/write curve. The loading speed is finally where it should be, and the system feels tight.