The same applies to lots of characters though. Chase scenes are pretty much won by the fastest. Do you not have monks or barbarians or wood elves in your group? Heck, a monk/rogue is massively faster than a tabaxi. You get an extra 30 feet of movement, once. How is this bypassing anything? Again, in 10 rounds, that Tabaxi could potentially move 450 feet. My monk/rogue does the same distance in 4 rounds and never has to stop moving. Totally not seeing the issue here.Any time the pcs get to go on the offensive after someone or yo on the offensive after scouting initiative can start where the players do something to appear hostile... And 5e gives them ample tools to make that happen at a range of hundreds of feet, that was why I mentioned ranges. Every time reinforcements are coming or opponents are running that move speed trivializes things. Likewise with every chase scene is simply "no I win" unless the distance is extreme or reasons are created to duesexmschina the whole thing if the nontabaxi players ever had a chance. There is also like I said before the fact that the tabaxi speed allows them to completely bypass front line types if indoor rooms aren't filled like a clown car, I think you missed the significance of that because you likely take a different view of 5e's unforgivably atrocious grid combat support than I do.
Mounts are not an issue because unlike the legs of a playerthey have so many weakness including being very obvious low hp bad saves can be spooked are big have grazing or similar needs etc.
I mean, you're talking about starting the encounter from 300 feet. A Tabaxi closes that distance at exactly the same speed as any other character. Maybe gets there one round early because of a single bonus 30 feet. I mean, the barbarian has a base movement of 40. Your Tabaxi in the first round moves 90 feet, my barbarian moves 80. Second round, tabaxi moves 60 feet (total 150) and the barbarian moves 160.
How is this a problem? I could see bigger issues with the climb speed since that lets a tabaxi character totally bypass many challenges. But a bonus 30 feet of movement every other round? Whoopee.