While some might be tempted to call these ships dated by the standards of more modern starships, their classic hull configurations and resilient internal specifications allow them to remain strong front-line contenders in any deep space exploration assignment or armed conflict.
Fine.. O'Brien and Geordi's revolutionary modular ship construction system has made the need to completely phase out old hulls more or less obsolete. Tier 5-up away.
Just...just don't go too overboard. Be not blinded by nostalgia nerds, keep the torch burning for spiffy new 25th-century designs.