Defense in depth will be important for Ukraine, as it has been been throughout the war. Russia has has proven time and again thay everytime they advance in a region they become stretched too thin, have their logistics and supplies targeted by Ukrainian long range weapons and they become immediately vulnerable to counter attack.
We saw it in Kyiv, when their 40km convoy was pushed back into Belarus, after experiencing extreme losses as a result of a logistics debacle.
We saw it in Kharkiv, where the entire Russian offensive collapsed and they lost hundreds of heavy vehicles to capture, in an unorganized, panicked retreat, as their logistics collapsed and they had to fall back to Luhansk.
We saw it in Kherson, when Russian supplies began to run out and the Russian Army was forced to retreat out of the entire region, rather than be trapped against the river.
We're seeing it in Bakhmut, where Russia is losing substantial ground north and south of the city in a matter of weeks, that took them 6-8 months to capture previously.
Ukraine will adjust, as they have throughout the conflict, and the casualties that Russia will endure will, again, be extremely heavy.
This is an oversimplification and overgeneralization of things, In the case of Northern Ukraine (Sumy-Kyiv) campaign, the Russian logistics are hampered by their failure to secure key cities and their own underestimation of the defending side. In Kharkiv, the lack of manpower and their complete lack of defensive lines helped Ukraine overcome the front, in Kherson the destruction of the main supply line like Kherson bridge severely hurt their ability to resupply.
None of which are present in the current frontline of Zaporizhia and most of the active frontline including Svatove. Where logistics are improved, fortifications are strengthened and in general the Russians has improved in their combat capability.
Also if have yet to notice, the HIMARS no longer are effective in destroying Russian munitions dump at the frontline like in their first 3 months of combat in Ukraine, as the Russians has already adapted long ago, HIMARS and its GMLRS are mostly used in the artillery killing role nowadays.